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mathematics | At what price must an article costing Rs.47.50 be marked in order that after deducting 10% from the list price. It may be sold at a profit of 25% on the cost price? | [
"60.5",
"65.9",
"67.5",
"62.5",
"22.5"
]
| CP = 47.50
SP = 47.50*(125/100) = 59.375
MP*(90/100) = 59.375
MP = 65.9
Answer:B
The answer is: B | B |
mathematics | If 2^y = 4^(5x + 3) and 3^(x - 7) = 9^y, what is the value of x + y ? | [
"-10",
"-5",
"-4",
"3",
"7"
]
| 2^y = 4^(5x + 3)
2^y=2^2(5x+3)
y=10x+6 ........... 1
3^(x - 7) = 9^y
3^(x-7)=3^2y
x-7=2y ............. 2
put value of y=10x+6 in eq 2
x-7=2(10x+6)
x-7=20x+12
19x=-19
x=-1
therefore, y= -10+6
y=-4
x+y= -1-4= -5
Answer: B
The answer is: B | B |
mathematics | A man taking the census walks up to the apartment of a mathematician and asks him if he has any children and how old they are. The mathematician says "I have three daughters and the product of their ages is 72." The man tells the mathematician that he needs more information, so the mathematician tells him "The sum of their ages is equal to our apartment number." The man still needs more information so the mathematician tells him "My oldest daughter has her own bed and the other two share bunk beds."
How old are his daughters? | [
"5-2-3",
"6-4-4",
"9-5-4",
"8-3-3",
"7-2-2"
]
| His daughters are 8, 3, and 3. The prime factorization of 72 is 2 * 2 * 2 * 3 * 3, so the possible ages are 2, 3, 4, 6, 8, 9, 12, and 18. Using the prime factorization and these numbers the only combinations of numbers that work for the first clue are:
18, 2 and 2.
9, 4 and 2.
6, 6 and 2.
6, 4 and 3.
8, 3, and 3.
Since he doesn't know the ages after this piece of information the sum of the three numbers must not be unique. The sum of 8, 3, and 3; and 6, 6, and 2 are the same. Now the final clue comes in handy. Since we know that the oldest daughter has her own bed it is likely that she has the bed to herself and is older than the other two so there ages are 8, 3, and 3 rather than 2, 6 and 6.
The answer is: D | D |
mathematics | A train covers a distance in 50 minutes, if it runs at a speed of 48kmph on an average. Find the speed at which the train must run to reduce the time of journey to 40 minutes. | [
"70 km/hr",
"60 km/hr",
"10 km/hr",
"20 km/hr",
"30 km/hr"
]
| Explanation:
We are having time and speed given, so first we will calculate the distance. Then we can get new speed for given time and distance.
Lets solve it.
Time = 50/60 hr = 5/6 hr
Speed = 48 mph
Distance = S*T = 48 * 5/6 = 40 km
New time will be 40 minutes so,
Time = 40/60 hr = 2/3 hr
Now we know,
Speed = Distance/Time
New speed = 40*3/2 kmph = 60kmph
Answer: B
The answer is: B | B |
mathematics | Find the compound interest accrued on an amount of Rs.14,800 at 13.5% p.a at the end of two years. (Round off your answer to nearest integer? | [
"Rs.4268",
"Rs.4290",
"Rs.4566",
"Rs.4266",
"Rs.4208"
]
| CI = 14800{ [ 1 + 13.5/100]2 - 1 }
= 14800 { [1 + 27/200]2 - 1
= 14800 { 2 + 27/200}{27/200}
= (74)[2 + 27/200](27) =
1998[2 + 27/200] = 3996 + 269.73 = Rs.4266
Answer:D
The answer is: D | D |
mathematics | If (4x + y)/(x + 4y) = 2/3, then find the value of (x + 4y)/(4x + y). | [
"3/8",
"3/4",
"3/2",
"3/6",
"3/8"
]
| Explanation:
Given, (4x + y)/(x + 4y) = 2/3
=> 3(4x + y) = 2(x + 4y)
=> 2x = y
.: (x + 4y)/(4x + y) = x + 4(2x)/(4x + 2x) = 9x/6x = 3/2
Answer: Option C
The answer is: C | C |
mathematics | A bus covers a distance of 12 km in 5 min. If it takes 5 sec to pass a telegraph post, then the length of the bus is? | [
"120m",
"180m",
"240m",
"200m",
"280m"
]
| Speed = (12/5 * 60) km/hr = (144 * 5/18) m/sec = 40 m/sec.
Length of the bus = 40 * 5 = 200 m.
ANSWER:D
The answer is: D | D |
mathematics | A car covers a distance of 424 km in 6 ½ hours. Find its speed? | [
"65.9 kmph",
"75.2 kmph",
"65.2 kmph",
"66.2 kmph",
"55.2 kmph"
]
| 424/(13/2) = 424*2/13
=65.2 kmph
ANSWER:C
The answer is: C | C |
mathematics | A computer program assigns consecutive numbers to the days of the week. Sunday is 1, Monday is 2, ..... and Saturday is 7. Every day, the computer program calculates the value of parameter D according to the following definition: D is the number of the day times the value of D on the previous day. If the computer calculated D to be 12 on Wednesday, what would be the value of D calculated on the following Saturday? | [
"2140",
"2520",
"2960",
"3360",
"3710"
]
| On Saturday, the value would be 7*6*5*12 = 2520
The answer is B.
The answer is: B | B |
mathematics | Find the amount on Rs.8000 in 9 months at 20% per annum, if the interest being compounded quarterly? | [
"1323",
"9261",
"2788",
"2999",
"1722"
]
| A = 8000(21/20)3 = 9261
Answer:B
The answer is: B | B |
mathematics | In a flight of 600 km, an aircraft was slowed down due to bad weather. Its average speed for the trip was reduced by 200 km/hr and the time of flight increased by 30 minutes. The duration of the flight is? | [
"1 hr",
"2 hr",
"6 hr",
"8 hr",
"7 hr"
]
| Let the duration of the flight be x hours. Then,
600/x - 600/(x + 1/2) = 200
x(2x + 1) = 3 2x2 + x - 3 = 0
(2x + 3)(x - 1) = 0
x = 1 hr.
Answer: A
The answer is: A | A |
mathematics | At a certain restaurant, the ratio of the number of cooks to the number of waiters is 3 to 10. When 12 more waiters are hired, the ratio of the number of cooks to the number of waiters changes to 3 to 13. How many cooks does the restaurant have? | [
"4",
"6",
"9",
"12",
"15"
]
| Originally there were 3k cooks and 10k waiters.
13k = 10k+12
k=4
There are 12 cooks.
The answer is D.
The answer is: D | D |
mathematics | If r and s are two different prime numbers, which of the following cannot be true? | [
"rs is odd.",
"r + s is even.",
"r + s is odd.",
"rs is even.",
"r/s is an integer"
]
| A prime number is a positive integer with exactly two distinct positive divisors: 1 and itself. So, a prime number cannot be a multiple of another prime number. Which makes option E not possible (r/s=integer means that r is a multiple of s).
.
All other options are possible:
A. rs is odd --> r=3 and s=5;
B. r + s is even --> r=3 and s=5;
C. r + s is odd --> r=2 and s=3;
D. rs is even --> r=2 and s=3;
Answer: E
The answer is: E | E |
mathematics | Ramu rides his bike at an average speed of 45 km/hr and reaches his desitination in four hours. Somu covers the same distance in five hours. If Ramu covered his journey at an average speed which was 9 km/hr less and Somu covered his journey at an average speed which was 10 km/hr more, then the difference in their times taken to reach the destination would be (in minutes). | [
"65 minutes",
"66 minutes",
"56 minutes",
"69 minutes",
"46 minutes"
]
| Distance travelled by Ramu = 45 * 4 = 180 km
Somu travelled the same distance in 5 hours.
His speed = 180/5 = 36 km/hr
Hence in the conditional case, Ramu's speed = 45 - 9 = 36 km/hr and Somu's speed = 36 + 10 = 46km/hr.
Therefore travel time of Ramu and Somu would be 5 hours and 3.9 hours respectively. Hence difference in the time taken = 1.1 hours = 66 minutes.
ANSWER:B
The answer is: B | B |
mathematics | The maximum number of students among them 1001 pens and 910 pencils can be distributed in such a way that each student gets the same number of pens and same number of pencils is: | [
"91",
"37",
"99",
"277",
"19"
]
| Explanation:
Required number of students = H.C.F of 1001 and 910 = 9
Answer: A) 91
The answer is: A | A |
mathematics | When the stock market opened yesterday, the price of a share of stock X was 10 1/2. When the market closed, the price was 11 1/4. Of the following, which is closest to the percent increase in the price of stock X? | [
"0.5%",
"1.0%",
"6.7%",
"7.1%",
"7.5%"
]
| General formula for percent increase or decrease, (percent change):
percent=Change/Original∗100
So, the percent increase in the price of stock X is (45/4−21/2)/(2/12)∗100=50/7
Answer: D.
The answer is: D | D |
mathematics | Sara's mother is 6 times older than Sara. Next year, however, she will be only 5 times older than her daughter. How old is Sara's mother. | [
"24 years",
"25 years",
"26 years",
"27 years",
"28 years"
]
| At the present,
Sara's age is x.
Sara's mother's age is y=6x.
Next year,
Sara's age will be x+1.
Sara's mother's age will be y+1=5(x+1).
From the two equations, we can calculate Sara's age:
y=6x
y+1=5 (x+1)
6x+1=5x+5
6x-5x=5-1
x=4
If Sara is currently 4 years old, and her mother is 6 times older, then her age is
6x=6×4=24.
ANSWER: A
The answer is: A | A |
mathematics | A train running at the speed of 70 km/hr crosses a pole in 9 sec. What is the length of the train? | [
"227 m",
"150 m",
"167 m",
"175 m",
"187 m"
]
| Speed = 70 * 5/18 = 175/9 m/sec
Length of the train = speed * time = 175/9 * 9
= 175 m
Answer: D
The answer is: D | D |
mathematics | A began business with Rs.45000 and was joined afterwards by B with Rs.27000. When did B join if the profits at the end of the year were divided in the ratio of 2:1? | [
"1",
"6",
"7",
"8",
"2"
]
| 45*12 : 27*x = 2: 1
x = 10
12 -10 = 2
Answer: E
The answer is: E | E |
mathematics | The number of new words that can be formed by rearranging the letters of the word 'ALIVE' is | [
"277",
"668",
"119",
"177",
"121"
]
| Number of words which can be formed
= 5! - 1 = 120 - 1 = 119.
Answer: C
The answer is: C | C |
mathematics | One copy machine can make 20 copies a minute, and a second copy machine makes 10 copies a minute. If the two copiers work together, how long would it take them to make 900 copies? | [
"10 minutes",
"20 minutes",
"25 minutes",
"30 minutes",
"35 minutes"
]
| Total work done by both machines in a minute = 20 + 10 = 30 copies
Total number of copies required = 900
Time = 900/30 = 30 mins
Answer D
The answer is: D | D |
mathematics | he two trains of lengths 400 m, 600 m respectively, running at same directions. The faster train can cross the slower train in 180 sec, the speed of the slower train is 48 km. then find the speed of the faster train? | [
"76 Kmph",
"68 Kmph",
"87 Kmph",
"56 Kmph",
"10 Kmph"
]
| Length of the two trains = 600m + 400m
Speed of the first train = X
Speed of the second train= 48 Kmph
1000/X - 48 = 180
1000/x - 48 * 5/18 = 180
50 = 9X - 120
X = 68 Kmph
Answer:B
The answer is: B | B |
mathematics | What is the next number in this sequence, 1, 11, 21, 1211, 111221 , 312211 ? | [
"1332123",
"1112321",
"2221313",
"1311222",
"3321233"
]
| D
Next in sequence is 13112221.
This series describes each number that came before it:
1 [One]
11 [One One]
21 [Two One(s)]
1211 [One Two and One One(s)]
111221 [One One, One Two, and Two One(s)]
312211 [Three One(s), Two Two(s), and One One]
The next number in the series is:
13112221 [One Three, One One, Two Two(s), Two One(s)]
The answer is: D | D |
mathematics | Find avrg speed if a man travels at speed of 15km/hr up and 28km/hr dawn at an altitude of 230m. | [
"25.8",
"19.5",
"18.0",
"12.2",
"29.8"
]
| avg speed=2*x*y/(x+y)
=2*15*28/(15+28)=19.5
ANSWER:B
The answer is: B | B |
mathematics | A trained covered x km at 30 kmph and another 2x km at 20 kmph. Find the average speed of the train in covering the entire 3x km. | [
"22.5",
"99",
"24",
"66",
"887"
]
| Total time taken = x/30 + 2x/20 hours
= 2x/15 hours
Average speed = 3x/(2x/15) = 22.5 kmph
Answer: A
The answer is: A | A |
mathematics | (0.76)(power 3) - (0.1)(power 3)/ (0.76)(power 2) + 0.076 + (0.1)(power 2) is: | [
"0.66",
"0.68",
"0.96",
"0.69",
"0.76"
]
| Given expression
= (0.76) (power 3) - (0.1)(power 3) / (0.76)(power 2) + (0.76 x 0.1) + (0.1)(power 2)
= a (power 3) - b(power 3) / a(power 2) + ab + b(power 2)
= (a - b)
= (0.76 - 0.1)
= 0.66
Answer is A.
The answer is: A | A |
mathematics | Josh spends a total of $5.5 buying A items in the convenience store. If each of the items is either a 5 cents single bubblegum, or a 50 cents bubblegum pack, then A may be which of the following? | [
"99",
"100",
"101",
"112",
"113"
]
| A items in the convenience store$5.5 = 550 cents
550 = 50a + 5b
=>110 = 10a + b
b = 110 - 10a = 10(11-a)
Hence b is even and multiple of 10.
Possible values of b:
b = 10,20,30,40,50,60,70,80,90,100
a = 11,9,8,7,6,5,4,3,2,1
The total (a+b) is 21,29,38,47,56,65,74,83,92,101
The only option is 101. Hence C.
The answer is: C | C |
mathematics | If "PROMPT" is coded as QSPLOS ,then "PLAYER" should be | [
"FKSKJH",
"DSKUIW",
"SHOUSA",
"QMBXDQ",
"SUISDUH"
]
| Explanation:
1st 3 letters are denoted by its next alphabet and the next 3 letters are denoted by its previous alphabets.
Answer: D
The answer is: D | D |
mathematics | A company produces 60000 bottles of water everyday. If a case can hold 5 bottles of water .How many cases are required by the company to hold its one day production | [
"12000",
"4500",
"5000",
"8000",
"9000"
]
| Number of bottles that can be held in a case = 5
Number of cases required to hold 60000 bottles = 60000/5=12000 cases.
So the answer is A =12000
The answer is: A | A |
mathematics | 16 men can do a piece of work in 16 days .4 days after they started the work, 8 more men joined them. How many days will they now take to complete the remaining work | [
"7 days",
"8 days",
"9 days",
"10 days",
"None of these"
]
| Solution:Work done by 1 man in 1 day=1/(16*16)
Work completed by 16 men in 4 days= 4[1/(16*16)]*16=1/4
Remaining work= 1- 1/4= 3/4
Total men now= 16+ 8=24
24 men do 3/4 work
=>24*number of days*Work done by 1 man in 1 day=3/4
=>24*number of days* 1/(16*16)=3/4
=>number of days=8 days
Answer B
The answer is: B | B |
mathematics | This topic is locked. If you want to discuss this question please re-post it in the respective forum.
Matt and Peter can do together a piece of work in 20 days. After they have worked together for 12 days Matt stops and Peter completes the remaining work in 14 days. In how many days Peter complete the work separately. | [
"26 days",
"27 days",
"23 days",
"35 days",
"24 days"
]
| Together they complete the job in 20 days means they complete 12/20 of the job after 12 days.
Peter completes the remaining (8/20) of the job in 14 days which means that the whole job(1) can be completed in X days.
<=> 8/20->14 <=> X=14/(8/20)=35Thus the answer is D.
The answer is: D | D |
mathematics | Average of 13 results is 65. If the average of first six results is 61 and average of last six results is 59 Then find the seventh result? | [
"120",
"123",
"125",
"128",
"130"
]
| 125
Option 'C'
The answer is: C | C |
mathematics | A certain school supplies store arranges pencils on display such that each of the six different colors of pencils, yellow, orange, green, red, blue, and purple are consecutive in a repeating pattern. If seven consecutively displayed pencils are purchased, what is the probability that two of the pencils
are purple? | [
"1/6",
"1/36",
"1/20",
"2/3",
"2/5"
]
| After yellow, orange, green, red, blue, and purple, the next pencil can be of any given six colours, therefore we have total six possibilites, out of which we need purple i.e. 1 therefore prob is 1/6.
The answer is: A | A |
mathematics | A graph may be defined as a set of points connected by lines called edges. Every edge connects a pair of points. Thus, a triangle is a graph of 3 edges and 3 points. The degree of a point is the number of edges connected to it. For, example, a triangle is a graph with 3 points of degree 2 each. Consider a graph with 12 points. It is possible to reach any point from any through sequence of edges. The number of edges 'e' in the graph must satisfy the condition | [
"11 ≤ e ≤ 66",
"10 ≤ e ≤ 66",
"11 ≤ e ≤ 65",
"0 ≤ e ≤ 11",
"None"
]
| Explanation :
The least number of edges will be when one point is connected to each of the other 11 points, giving a total of 11 lines. One can move from any point to any other point via the common point.
The maximum edges will be when a line exists between any two points. Two points can be selected from 12 points in 12C2 i.e. 66 lines.
Answer : A
The answer is: A | A |
mathematics | The remainder when A=1+3+3^2+3^3+..........+3^200 is divided 13. | [
"12",
"7",
"0",
"5",
"3"
]
| A=1+3+3^2+3^3+..................+3^200
Is a Geometric progression having common ratio as '3' and number of terms as '201'.
Since Sum to n terms in GP = a(r^n-1)/(r-1)
where a=First term and r =common ration
Hence,
1*(3^201 -1 )/(3-1)
Rem of (3^201-1)/2 divided by 13
3^201 -1 /26
WKT, 3^3 = 27 = 26+1
{(26+1)^67 - 1}/26
{1-1}/26
=>0.C
The answer is: C | C |
mathematics | Patrick is an avid star gazer and wants to make his own constellation. He is using a star chart that has 7 stars on it and decides that he will draw a continuous line using 3 of those 7 stars to make his constellation. There will be no closed shapes in his constellation. How many possible paths could his contstellation follow? | [
"15",
"21",
"97",
"210",
"980"
]
| This is a simple permutation calc
Permutation calc is: n P r = n! / (n-r)! 4 P 3 = 7!/(7-3)! = 7x6x5x(4x3x2x1)/4!=7X6X5=210 Correct answer is D (210)
The answer is: D | D |
mathematics | Sometime after 10:00 PM a murder took place. A witness claimed that the clock must have stopped at the time of the shooting. It was later found that the postion of both the hands were the same but their positions had interchanged. Tell the time of the shooting (both actual and claimed). | [
"10:59 PM",
"11:59 PM",
"10:50 PM",
"10:52 PM",
"10:55 PM"
]
| Actual time of shooting = 11:54 PM
Claimed Time = 10:59 PM
ANSWER:A
The answer is: A | A |
mathematics | Six family members are seated around their circular dinner table. If only arrangements that are considered distinct are those where family members are seated in different locations relative to each other, and Michael and Bobby insist on sitting next to one another, then how many distinct arrangements around the table are possible? | [
"48",
"56",
"64",
"72",
"80"
]
| Let's consider Michael and Bobby as one unit.
There are 5! possible arrangements of 5 units.
Around a table, there would be repetitions of each arrangement, so we divide by 5.
Then there are 4! arrangements around a circular table.
For each arrangement, Michael and Bobby can switch places, so we multiply by 2.
The number of arrangements is 4!*2 = 48.
The answer is A.
The answer is: A | A |
mathematics | The average weight of a group of boys is 30 kg. After a boy of weight 39 kg joins the group, the average weight of the group goes up by 1 kg. Find the number of boys in the group originally ? | [
"4",
"8",
"5",
"2",
"9"
]
| Let the number off boys in the group originally be x.
Total weight of the boys = 30x
After the boy weighing 39 kg joins the group, total weight of boys = 30x + 39
So 30x + 39 + 31(x + 1) = > x = 8.
Answer: B
The answer is: B | B |
mathematics | Two pipes A and B can separately fill a cistern in 10 and 15 minutes respectively. A person opens both the pipes together when the cistern should have been was full he finds the waste pipe open. He then closes the waste pipe and in another 4 minutes the cistern was full. In what time can the waste pipe empty the cistern when fill? | [
"1/4",
"1/7",
"2/4",
"2/3",
"1/3"
]
| 1/10 + 1/15 = 1/6 * 4 = 2/3
1 - 2/3 = 1/3
1/10 + 1/15 - 1/x = 1/3
x = 8
ANSWER:E
The answer is: E | E |
mathematics | Three unbased coins are tossed. the probability of getting at most three T is ? | [
"1/2",
"7/8",
"3/4",
"1/8",
"2/3"
]
| S={TTT,TTH,THT,HTT,THH,HTH,HHT,HHH}
E be the event of getting at least two head is {TTT}
P(E)=n(E)/n(S)=1/8
Answer(D)
The answer is: D | D |
mathematics | Which of the following is equal to the value of 2^4 + 2^4 + 3^4 + 3^4 + 3^4 ? | [
"2^5 + 3^10",
"2^5 + 3^9",
"2^5 + 3^8",
"2^5 + 3^5",
"2^5 + 3^7"
]
| 2^4 + 2^4 + 3^4 + 3^4 + 3^4
= 2 (2^4) + 3 (3^4)
= 2^1 (2^4) + 3^1 (3^4)
= 2^(1+4) + 3^(1+4)
= 2^5 + 3^5
Ans: D
The answer is: D | D |
mathematics | Kamal bought a house, whose sale price was Rs. 8 lakh. He availed 20% discount as an early bird offer and then 10% discount due to cash payment. After that he spent 10% of the cost price in interior decoration and lawn of the house. At what price should he sell the house to earn a profit of 25%? | [
"Rs. 9 lakh",
"Rs. 7.99 lakh",
"Rs. 7.92 lakh",
"Rs. 7 lakh",
"None of These"
]
| Solution: Let the marked price be 100.
100 == 20% ↓(discount)==> 80 == 10% ↓(discount)==> 72(CP) == 10% ↑(interior)==> 79.2(Total CP)
Now, selling price would be 25% above the Total cost price.
SP = 79.2 + 25% of 79.2
SP = 99
Now, On comparing,
100 ==> 800000
99 ==> (800000/100) *99 ==> 7, 92,000
So,
SP = Rs. 7, 92, 000.
Answer: Option C
The answer is: C | C |
mathematics | Present ages of Abi and Suji are in the ratio of 5:4 respectively. Three years hence, the ratio of their ages will become 11:9 respectively. What is Suji's present age in years? | [
"20",
"21",
"22",
"23",
"24"
]
| present ages = 5x:4x
Three hence =5x+3:4x+3
5x+3:4x+3=11:9
weget x=6
suji age is =4x=4*6=24
ANSWER:E
The answer is: E | E |
mathematics | Find the least number must be subtracted from 105829 so that remaining no.is divisible by 21? | [
"7",
"10",
"20",
"32",
"35"
]
| On dividing 105829 by 21 we get the remainder 10, so 10 should be subtracted
Answer is B
The answer is: B | B |
mathematics | Nine carpenters can individually complete a particular task in 3, 4, 5, and 7 hours, respectively. What is the maximum fraction of the task that can be completed in forty-five minutes if eight of the carpenters work together at their respective rates ? | [
"11/15",
"3/5",
"11/30",
"47/135",
"5/9"
]
| Farmer A, B, C, and D
A's rate: 1/3 job/hour
B's rate: 1/4 job/hour
C's rate: 1/5 job/hour
D's rate: 1/7 job/hour
By intuition we know that the three fastest farmers are A B and C.
As such
(1/3 + 1/4 + 1/5)*(8/9) = ?
47/135 or (D)
The answer is: D | D |
mathematics | In a camp, there is a meal for 120 men or 200 children. If 110 children have taken the meal, how many men will be catered to with remaining meal? | [
"30",
"20",
"40",
"57",
"54"
]
| There is a meal for 200 children.
110 children have taken the meal.
Remaining meal is to be catered to 90 children.
Now, 200 children 120 men.
90 children = (120/200)x 90 = 54 men.
E
The answer is: E | E |
mathematics | A train 125 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 10 sec. The speed of the train is? | [
"28",
"50",
"99",
"121",
"81"
]
| Speed of the train relative to man = 125/10 = 25/2 m/sec.
= 25/2 * 18/5 = 45 km/hr
Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr.
x - 5 = 45 => x = 50 km/hr.
Answer: B
The answer is: B | B |
mathematics | Working alone at their respective constant rates, A can complete a task in ‘a’ days and B in ‘b’ days. They take turns in doing the task with each working 2 days at a time. If A starts they finish the task in exactly 14 days. If B starts, they take a day more. How long does it take to complete the task if they both work together? | [
"12",
"14",
"10",
"11",
"13"
]
| Work done by AB in a day = xy respectively.
When A starts:
No. of days when A works = 8No. of days when B works = 6 → 8x + 6y = 1
When B starts:
No. of days when A works = 7No. of days when A works = 7 → 7x + 7y = 1
Solving the above two equations for xy
x = 1/14 y = 1/14
→ Total work done by AB in a day = 1/14 + 1/14 = 2/28= 1/14
→ No. of days to complete the work when both work together =14
Answer: B
The answer is: B | B |
mathematics | Mr X, a businessman, had income in the year 1995 such that he earned a profit of 20% on his investment in the business. In the year 1996 his investment was less by 2000 but still had the same income (Income = Investment + Profit) as that in 1995. Thus the per cent profit earned in 1996 increased by 6%. What was his investment in 1995? | [
"100000",
"12500",
"42000",
"Data inadequate",
"None of these"
]
| Let the investment of X in 1995 be x.
∴ Profit = x⁄5
∴ Income = (x + x⁄5) = 6⁄5x
Investment of company X in 1996 would be (x – 2000) From the question,
(x - 2000) × 126⁄100 = 6⁄5x ⇒ x = 42000
Answer C
The answer is: C | C |
mathematics | A train travels at an average of 40 miles per hour for 4 hours and then travels at a speed of 60miles per hour for 2hours. How far did the train travel in the entire 6 hours? | [
"100miles",
"150miles",
"200miles",
"250miles",
"300miles"
]
| Total distance traveled = (40*4)+(70*2) = 160+140 = 300 miles
Answer is E
The answer is: E | E |
mathematics | In a sequence, each term is obtained by adding 7 to the preceding one. If the sum of the first 30 terms is equal to 705, what is the result of the addition of the first 40 terms? | [
"2000",
"2250",
"2340",
"2400",
"2440"
]
| a is first term and d = 7 since the preceding number is always greater than the previous one..
Now 30th term is a+29(7).
Sum of n terms is n/2(first term + last term)and here we have to get sum of 30 terms , we get 30/2 ( a + a+203) = 705 ( given sum of 30 terms is 705)
=> 15(2a+203) = 705
=> 2a+203 = 47
=> 2a=-156
=> a = -78
Now to get sum of first 40 terms , we need to get 40th term value i.e. -78+39(7) = 195.
Sum of first 40 terms = 40/2( -78 + 195) =2340 .
Hence option C is correct answer..
The answer is: C | C |
mathematics | In what time a sum of money double itself at 4% per annum simple interest? | [
"33 1/8%",
"33 1/3%",
"33 7/3%",
"32 1/3%",
"25 %"
]
| P = (P*4*R)/100
R = 25%
Answer: E
The answer is: E | E |
mathematics | A certain city with a population of 60,000 is to be divided into 11 voting districts , and no district is to have a population that is more than 10 percent greater than the population of any other district What is the minimum possible population that the least populated district could have ? | [
"a) 10,700",
"b) 10,800",
"c) 10,900",
"d) 11,000",
"e) 5,000"
]
| Let x = number of people in smallest district
x*1.1 = number of people in largest district
x will be minimised when the number of people in largest district is maximised
10*x*1.1 = 11x = total number of people in other districts
So we have 11x + x = 60k
x = 5,000
Answer : E
The answer is: E | E |
mathematics | In a tennis match if the first serve is not legal, that means a fault a second serve is allowed. Normally, 20 to 40 serves are required in a set of tennis match. At the end of a set, set summary stats reveal that first serves percentage was 63%. If m out of n were first serves then m + n is equal to | [
"1.43n",
"1.53n",
"1.63n",
"2.63n",
"3.63n"
]
| m=n*(63/100)=63n/100
so,
m+n= 63n/100 + n
= 163n/100
= 1.63n
ANSWER:C
The answer is: C | C |
mathematics | If selling price is doubled, the profit triples. Find the profit percent: | [
"66 2/3",
"100",
"105 1/3",
"120",
"150"
]
| Let C.P. be Rs. x and S.P. be Rx. y.
Then, 3(y - x) = (2y - x) => y = 2x
Profit = (y - x) = Rs. (2x - x) = Rs. x
Profit % = x/x * 100 = 100%.
ANSWER:B
The answer is: B | B |
mathematics | If P is a prime number greater than 3, find the remainder when P^2 + 15 is divided by 12. | [
"6",
"4",
"0",
"8",
"7"
]
| Every prime number greater than 3 can be written 6N+1 or 6N-1.
If P = 6N+1, then P^2 + 15 = 36N^2 + 12N + 1 + 15 = 36N^2 + 12N + 12 + 4
If P = 6N-1, then P^2 + 15 = 36N^2 - 12N + 1 + 15 = 36N^2 - 12N + 12 + 4
When divided by 12, it must leave a remainder of 4.
The answer is B.
The answer is: B | B |
mathematics | What is the sum of all possible solutions to |x - 4|^2 + |x - 4| = 12 ? | [
"3",
"4",
"5",
"6",
"7"
]
| Denote |x - 4| as y: y^2 + y = 12 --> y = -4 or y = 3. Discard the first solution since y = |x - 4|, so it's an absolute value and thus cannot be negative.
y = |x - 4| = 3 --> x = 7 or x = 0. The sum = 7.
Answer: E.
The answer is: E | E |
mathematics | Two trains are running in opposite directions with the same speed. If the length of each train is 120 m and they cross each other in 6 sec, then the speed of each train is? | [
"30",
"31",
"72",
"25",
"24"
]
| Let the speed of each train be x m/sec.
Then, relative speed of the two trains = 2x m/sec.
So, 2x = (120 + 120)/6 => x = 20
Speed of each train = 20 m/sec.
= 20 * 18/5 =72km/hr.
Answer: Option C
The answer is: C | C |
mathematics | A cistern can be filled by a tap in 4 hours while it can be emptied by another tap in 8 hours. If both the taps are opened simultaneously, then after how much time will the cistern get filled? | [
"7.5",
"7.4",
"7.9",
"7.2",
"8.0"
]
| Net part filled in 1 hour = (1/4 - 1/9) = 1/8
The cistern will be filled in 8/1 hrs i.e., 8 hrs.Answer: E
The answer is: E | E |
mathematics | A boy was asked to multiply a number by 22. He instead multiplied the number by 44 and got the answer 308 more than the correct answer. What was the number to be multiplied? | [
"16",
"10",
"14",
"12",
"8"
]
| Explanation :
Let the number be x
22x + 308 = 44x
=> 44x - 22x = 308
=> 22x = 308
=> x = 308/22 = 154/11 = 14
Answer : C
The answer is: C | C |
mathematics | A 150 metres long train running at the speed of 120 kmph crosses another train running in opposite direction at the speed of 80 kmph in 9 seconds. What is the length of the other train? | [
"220 meter",
"225 meter",
"230 meter",
"350 meter",
"None of these"
]
| Explanation:
As trains are running in opposite directions so their relative speed will get added
So, Relative speed = 120 +80 = 200 kmph
= 200*(5/18) = 500/9 m/sec
Let the length of other train is x meter then
x+150 /9=500 /9
=>x+150=500
=>x=350
So the length of the train is 350 meters
Option D
The answer is: D | D |
mathematics | An article is bought for Rs.675 and sold for Rs.900, find the gain percent? | [
"33 1/8%",
"33 3/3%",
"33 1/3%",
"39 1/3%",
"33 4/3%"
]
| 675 ---- 225
100 ---- ? => 33 1/3%
Answer:C
The answer is: C | C |
mathematics | Three candidates contested an election and received 1136, 7636 and 12000 votes respectively. What percentage of the total votes did the winning candidate get? | [
"46%",
"58%",
"74%",
"63%",
"68%"
]
| B
12000/(1136 + 7636 + 12000) = 58%.
The answer is: B | B |
mathematics | Can you solve the alphametic?
ENLIST + SILENT + LISTEN = ANAGRAM | [
"1816412",
"1416312",
"1516312",
"1216312",
"1116312"
]
| Correct Answer : B
assume numeric values for alphabetics. like a=0, b=1, c=2, c=3, d=4, e=5,...
solution
547809+087549+780954 = 1416312
The answer is: B | B |
mathematics | The average salary of all the workers in a workshop is Rs.8000. The average salary of 7 technicians is Rs.10000 and the average salary of the rest is Rs.6000. The total number of workers in the workshop is | [
"20",
"21",
"22",
"23",
"14"
]
| Solution
Let the toatl number of workers be x.
Then 8000x=(10000 x 7) + 6000 (x -7)
x= 14.
Answer E
The answer is: E | E |
mathematics | A five-digit number divisible by 3 is to be formed using numerical 0, 1, 2, 3, 4 and 5 without repetition. The total number E of ways this can be done is: | [
"122",
"210",
"216",
"217",
"225"
]
| We should determine which 5 digits from given 6, would form the 5 digit number divisible by 3.
We have six digits: 0, 1, 2, 3, 4, 5. Their sum=15.
For a number to be divisible by 3 the sum of the digits must be divisible by 3. As the sum of the six given numbers is 15 (divisible by 3) only 5 digits good to form our 5 digit number would be 15-0={1, 2, 3, 4, 5} and 15-3={0, 1, 2, 4, 5}. Meaning that no other 5 from given six will total the number divisible by 3.
Second step:
We have two set of numbers:
1, 2, 3, 4, 5 and 0, 1, 2, 4, 5. How many 5 digit numbers can be formed using these two sets:
1, 2, 3, 4, 5 --> 5! as any combination of these digits would give us 5 digit number divisible by 3. 5!=120.
0, 1, 2, 4, 5 --> here we can not use 0 as the first digit, otherwise number won't be any more 5 digit and become 4 digit. So, desired # would be total combinations 5!, minus combinations with 0 as the first digit (combination of 4) 4! --> 5!-4!=4!(5-1)=4!*4=96
120+96=216=E
Answer: C.
The answer is: C | C |
mathematics | The ratio of the earnings of P and Q is 9 : 10. If the earnings of P increases by one-fourth and the earnings of Q decreases by one-fourth, then find the new ratio of their earnings? | [
"3/6",
"3/2",
"3/9",
"3/1",
"3/5"
]
| Let the earnings of P and Q be Rs. 9x and Rs. 10x respectively.
New ration = [9x + 1/4(9x)]/[10x - 1/4(10x)]
=> [9x(1 + 1/4)]/[10x(1 - 1/4)] = 9/10 * (5/4)/(3/4)
=> 3/2.
Answer: B
The answer is: B | B |
mathematics | How many of the positive divisors Q of 120 are also multiples of 4 not including 120? | [
"3.",
"4.",
"5.",
"7.",
"8."
]
| 4,8,12,20,24,40,60. (7) is the answer
Other way : factors of 120 = 2^3 * 3*5
Separate 2^2 ( which means 4)
Now, calculate the number of other factors.
Q=2*3*5 = total positive factors are 2*2*2 = 8
This 8 factors include 120
So subtract 1 from 8
Ans is 7=D
The answer is: D | D |
mathematics | 25% of a number is more than 20% of 650 by 190. Find the number? | [
"288",
"278",
"800",
"267",
"1280"
]
| (25/100) * X – (20/100) * 650 = 190
1/4 X = 320
X = 1280
Answer:E
The answer is: E | E |
mathematics | In what time will a train 175 m long cross an electric pole, it its speed be 180 km/hr? | [
"7.5",
"6.5",
"5.5",
"4.5",
"3.5"
]
| Speed = 180 * 5/18 = 50 m/sec
Time taken = 175/50 = 3.5 sec.
Answer: E
The answer is: E | E |
mathematics | A teacher will pick a group of 4 students from a group of 8 students that includes Lisa. If one of all the possible four-student groups is picked at random, what is the probability of picking a group that includes Lisa? | [
"1/7",
"3/14",
"1/2",
"1/3",
"3/7"
]
| Probability = Favorable Outcomes / Total Outcomes
Total Outcomes= Total No. of ways of Picking Group of 4 out of 8 = 8C4 = 8! / (4! * 4!) = 70
Favorable Outcomes= Total No. of ways of Picking Group of 4 out of 8 such that L is always in the group (i.e. we only have to pick remaining 3 out of remaining 7 as L must be there in group) = 7C3 = 35
Hence,Probability=35/70=1/2
Answer: Option C
The answer is: C | C |
mathematics | If s,u, and v are positive integers and 2s=u+2v, which of the following must be true?
i. u>v
ii. u is not equal to v
iii. s=u | [
"None",
"I only",
"II only",
"III only",
"II and III"
]
| Notice two things: 1. we are asked to find out which of the following MUST be true, not COULD be true and 2. s, u, and v are positive integers.
Given: 2s=2u+2v --> s=u+v. Now, since s, u, and v are positive integers then s is more than either u or v, so I is never true and III is always true. As for II: it's not necessarily true, for example 4=2+2. So, we have that only option I must be true.
Answer: B
The answer is: B | B |
mathematics | 90% of the population of a village is 36000. The total population of the village is? | [
"26799",
"24000",
"26682",
"29973",
"40000"
]
| X * (90/100) = 36000
X = 400 * 100
X = 40000
Answer: E
The answer is: E | E |
mathematics | If n is a positive integer and the product of all integers from 1 to n, inclusive, is a multiple of 440, what is the least possible value of n? | [
"10",
"11",
"12",
"13",
"14"
]
| is it 11 ?
440 = 2 * 2 * 2 * 5 * 11
so the least value forNcan be 11.
B
The answer is: B | B |
mathematics | There are three places P, Q and R such that 3 roads connects P and Q and 4 roads connects Q and R. In how many ways can one travel from P to R? | [
"32",
"75",
"12",
"51",
"47"
]
| Number of ways in which one can travel from P to R
=3×4=12=3×4=12
Ans: C
The answer is: C | C |
mathematics | In how many different ways could couples be picked from 8 men and 5 women? | [
"8",
"5",
"13",
"40",
"20"
]
| Number of mens = 8
Number of womens = 5
Different ways could couples be picked = 8c1 * 5c1 = 8 * 5 = 40 ways
ANSWER:D
The answer is: D | D |
mathematics | A boy goes to his school from his house at a speed of 3 km/hr and returns at a speed of 2 km/hr. If he takes 5 hours in going and coming. The distance between his house and school is? | [
"7 km",
"3 km",
"6 km",
"9 km",
"2 km"
]
| Average speed = (2 * 3 * 2) / (3 + 2)
= 12/5 km/hr.
Distance traveled = 12/5 * 5 = 12 km.
Distance between house and school
= 12/2
= 6 km.
Answer: C
The answer is: C | C |
mathematics | Line J has a y-intercept of 7 and passes through point (a,b). What is the slope of Line J in terms of a and b? | [
"(b-7)/a",
"(a−b)/6",
"(6−a)/b",
"(6−b)/a",
"(b−6)/a"
]
| You know that the line goes through point (a,b) and the y-intercept of 7 tells you that the line also goes through point (0,7).
slope m = (y-y1)/(x-x1) = (b-7)/(a-0)
A
The answer is: A | A |
mathematics | The ages of 2 persons differ by 16 years. If 6 years ago the elder one be 3 times as old as the younger one, find the present age of younger person. | [
"10",
"14",
"20",
"15",
"32"
]
| age of the younger person = x
age of the elder person = x+16
3(x-6) = x+16-6
x= 14
Answer is B
The answer is: B | B |
mathematics | Of the 100 athletes at a soccer club, 40 play defense and 64 play midfield. If at least 20 of the athletes play neither midfield nor defense, the number of athletes that play both midfield and defense could be any number between | [
"10 to 20",
"10 to 40",
"24 to 40",
"30 to 70",
"40 to 70"
]
| First of all notice that since only 40 athletes play defense, then the number of athletes that play both midfield and defense cannot possibly be greater than 40.Eliminate D and E.
{Total} = {defense} + {midfield} - {both} + {neither}
100 = 40 + 64 - {both} + {neither}
{both} = {neither} + 4.
Since the least value of {neither} is given to be 20, then the least value of {both} is 20+4=24.Eliminate A and B.
Answer: C.
The answer is: C | C |
mathematics | The sector of a circle has radius of 21 cm and central angle 135o. Find its perimeter? | [
"23.9 cm",
"62.9 cm",
"91.5 cm",
"26.8 cm",
"16.8 cm"
]
| Perimeter of the sector = length of the arc + 2(radius)
= (135/360 * 2 * 22/7 * 21) + 2(21)
= 49.5 + 42
= 91.5 cm
Answer:C
The answer is: C | C |
mathematics | In particular old age home, 60% are suffering from diabetic and at the same time 80% are suffering from blood pressure.If suppose 75% are suffering from diabetic,what percentage of old people suffering from blood pressure at the same old age home? | [
"23",
"16",
"26",
"36",
"20"
]
| given : % of people suffering from diabetics = 60%; % of people suffering from blood pressure = 80% (ie ) 0.8
total =75*100; Those who are suffering from diabetics= 75 - 60 = 15; Those who are suffering from blood pressure =
100 - 80=20; so those who are suffering from blood pressure =0.8*20=16; Total number of people suffering from blood pressure = 20+16 = 36. Answer: D
The answer is: D | D |
mathematics | The wages earned by Robin is 30% more than that earned by Erica. The wages earned by Charles is 60% more than that earned by Erica. How much percent is the wages earned by Charles more than that earned by Robin? | [
"18.75%",
"23%",
"30%",
"50%",
"100%"
]
| Let wage of Erica = 10
Wage of Robin = 1.3*10 = 13
Wage of Charles = 1.6 *10 = 16
Percentage by which wage earned by Charles is more than that earned by Robin = (16-13)/13 * 100%
= 3/13 * 100%
=23%
Answer B
The answer is: B | B |
mathematics | Find the invalid no.from the following series 15, 17, 34, 105, 424, 2124, 12756 | [
"17",
"34",
"105",
"424",
"2124"
]
| 2nd term = (1st term) * 1 + 1 = 15 *1 + 1 = 16.
3rd term = (2nd term) * 2 + 2 = 16 * 2 + 2 = 34
4th term = (3th term) *3 + 3 = 34 * 3 + 3 = 105
5th term = (4th term) * 4 + 4 = 105 * 4 + 4 = 424
6th term = (5th term) * 5 + 5 = 424 * 5 + 5 = 2125
2nd term should 16 instead of 17.
A
The answer is: A | A |
mathematics | Find the odd man out
1,25, 31,37, 127, 503, | [
"503",
"37",
"31",
"1",
"25"
]
| 25 is square of 5 which is a square number where as all others are prime numbers.
ANSWER:E
Correct Option: C) E . Answer : E
The answer is: E | E |
mathematics | How many minutes does it take John to type z words if he types at the rate of y words per minute? | [
"z/y",
"y/x",
"xy",
"60x/y",
"y/(60x)"
]
| time*rate=job --> time*y=z --> time=z/y.
Answer: A.
The answer is: A | A |
mathematics | How many times the keys of a typewriter have to be pressed in order to write first 400 counting numbers? | [
"2388",
"1092",
"2788",
"1192",
"1901"
]
| Explanation:
1 to 9 = 9 * 1 = 9
10 to 99 = 90 * 2 = 180
100 to 400 = 301 * 3 = 903
-----------
1092
Answer: B
The answer is: B | B |
mathematics | The average weight of 10 girls increases by 5 kg when a new girl comes in place of one of them weighing 50 kg. What might be the weight of the new girl? | [
"90 kg",
"100 kg",
"95 kg",
"85 kg",
"92 kg"
]
| Total weight increased = 10 x 5 kg = 50 kg.
Weight of new person = 50 + 50 kg =100 kg
Answer : B
The answer is: B | B |
mathematics | When positive integer m is divided by positive integer x, the reminder is 7 and when positive integer n is divided by positive integer y, the reminder is 11. Which of the following E is a possible value for x + y?
I. 18
II. 19
III. 20 | [
"I only",
"II only",
"E=III only",
"II and III only",
"None"
]
| TIP FOR SUCH QUESTIONS:Make Algebraic Equation in the beginning to understand how to proceed further. Then Start thinking the possible values of variables asked about
i.e.When positive integer m is divided by positive integer x, the reminder is 7can be understood as
m = ax +7which means thevalue of x must be greater than 7as the remainder 7 is possible only when the Divisor is bigger than the Remainder 7
i.e. Min Value of x = 8
AND
i.e.When positive integer n is divided by positive integer y, the reminder is 11can be understood as
n = by +11which means thevalue of y must be greater than 11as the remainder 11 is possible only when the Divisor is bigger than the Remainder 11
i.e. Min Value of y = 12
i.e. Minimum Value of x+y = 8+12 = 20
Hence III only can be True
Answer: Option
C
The answer is: C | C |
mathematics | Solve:-
666 x 666 x 666 + 555 x 555 x 555 = ?(666 x 666 - 666 x 555 + 555 x 555) | [
"888",
"333",
"555",
"1221",
"889"
]
| Given Exp. = (a3 + b3) = (a + b) = (666 + 555) = 1221(a2 - ab + b2)
Answer D
The answer is: D | D |
mathematics | If a,b, and c are consecutive positive integers and a>b>c, what can be the value of (a^2-b^2)(b^2-c^2)? | [
"100",
"110",
"121",
"132",
"143"
]
| (a^2-b^2)(b^2-c^2) = (a+b)*(a-b)*(b+c)*(b-c) = (a+b)*(-1)*(b+c)*(-1) = (a+b)*(b+c)
Therefore, the product should have factors with a difference of 2.
143 = 11*13, so this is a possible value for the original expression.
The answer is E.
The answer is: E | E |
mathematics | The smallest ratio out of 1:1, 2:1, 1:3,4:1 and 3:1 is? | [
"1:1",
"1:3",
"2:1",
"3:1",
"4:1"
]
| 1/1=1
1/3=0.333
2/1=2
3/1=3
4/1=4
ANSWER:B
The answer is: B | B |
mathematics | A, B and C play a cricket match. The ratio of the runs scored by them in the match is A:B = 2:4 and B:C = 2:5. If the total runs scored by all of them are 100, the runs scored by B are? | [
"20.23",
"20.13",
"30.93",
"25",
"10.93"
]
| A:B = 2:4
B:C = 2:5
A:B:C = 4:8:20
8/32 *100 = 25
ANSWER:D
The answer is: D | D |
mathematics | Three people (1 couple and 1 single) are seated at random in a row of 6 chairs. What is the probability that the couple does not sit together? | [
"2/3",
"4/5",
"2/7",
"3/5",
"5/12"
]
| The total number of arrangements of 3 people is 6*5*4 = 120
Let's think of the couple as a single unit.
The number of arrangements when the couple sits together is 5*4*2 = 40.
Note that we multiply by 2 because the couple can switch places with each other.
The number of ways the couple won't sit together is 120 - 40 = 80
P(couple won't sit together) = 80/120 = 2/3
The answer is A.
The answer is: A | A |
mathematics | An employee’s annual salary was increased 30%. If her old annual salary equals $30,000 , what was the new salary? | [
"$28,000",
"$25,000",
"$20,000",
"$35,000",
"$39,000"
]
| Old annual salary = $30,000
Salary increase = 30%.
Original salary = $30,000 *30/100
= $9000
new salary = $30,000+$9000
=$39,000
Hence E.
The answer is: E | E |
mathematics | At a local supermarket, a box of cereal usually costs 22 dollars. This week, the supermarket sells the box of cereal for 11 dollars. How much money will you save if you buy this cereal at this supermarket? | [
"11 dollars",
"13 dollars",
"14 dollars",
"12 dollars",
"10 dollar"
]
| Solution:
In this situation, there is a decrease in the price.
Saving = 22 - 11 = 11 dollars
Option A
The answer is: A | A |
mathematics | A customer asks the clerk for a paintbrush and a bucket of whitewash for a total price of B dollars. If the paintbrush costs 700 cents less than twice the price of a bucket of whitewash, what is the price of half a bucket of whitewash in dollars? | [
"(B + 200)/2.",
"(B + 2)/6.",
"(2B + 200)/3.",
"(B + 2)/3.",
"(B - 2)/6."
]
| P = 2w - 200
thus total price in cents as given should be
2w-200 +w = 100B
3w - 200 = 100 B
3w = 100 B+200
3w =b+2 (in dollars)
w/2 = (b+2)/6
Ans:C
The answer is: C | C |
mathematics | In how many different ways can the letters of the word 'OPTICAL' be arranged so that the vowels always come together? | [
"520",
"720",
"890",
"870",
"1098"
]
| The word 'OPTICAL' contains 7 different letters.
When the vowels OIA are always together, they can be supposed to form one letter.
Then, we have to arrange the letters PTCL (OIA).
Now, 5 letters can be arranged in 5! = 120 ways.
The vowels (OIA) can be arranged among themselves in 3! = 6 ways.
Required number of ways = (120 x 6) = 720.
ANSWER B 72
The answer is: B | B |
mathematics | Two numbers are in the ratio 3 : 4. If their L.C.M. is 72. what is sum of the numbers? | [
"42",
"56",
"76",
"84",
"85"
]
| Explanation:
Let the numbers be 3x and 4x
LCM of 3x and 4x = 12x (Since LCM of 3 and 4 is 12. Hence LCM of 3x and 4x is 12x)
Given that LCM of 3x and 4x is 72
=> 12x = 72
=> x = 72/12 = 6
Sum of the numbers
= 3x + 4x
= 7x
= 7 x 6 = 42
Answer: Option A
The answer is: A | A |
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