RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: A boat running downstream covers a distance of 22 km in 4 hours while for covering the same distance upstream, it takes 5 hours. What is the speed of the boat in still water?
A.5 kmph
B.4.95 kmph
C.4.75 kmph
D.4.65
Answer: B.4.95 kmph
Explanation: Explanation :
Speed downstream = 22/4 = 5.5 kmph
Speed upstream = 22/5 = 4.4 kmph
Speed of the boat in still water = (5.5 + 4.4)/2 = 4.95 kmph. Answer : Option B
Question: he average of 15 numbers is zero. Of them, at the most, how many may be greater than zero?
A.0
B.1
C.14
D.19
Answer: C.14
Explanation: Average of 15 numbers = 0.
Sum of 15 numbers (0 x 15) = 0.
It is quite possible that 14 of these numbers may be positive and if their sum is a the 15th number is (-a).
Answer: Option C
Question: a vase has 2 dozens of assorted flowers of which 8 are daisies. what is the ratio of the daisies to the whole arrangement?
A.1/2
B.1/3
C.1/12
D.8/12
Answer: B.1/3
Explanation: 2 dz flowers=24; ratio of daisies to the whole flower arrangement is 8/24=1/3
ANSWER:B
Question: A can do a piece of work in 15 days. A does the work for 5 days only and leaves the job. B does the remaining work in 16 days.In how many days B alone can do the work?
A.5days
B.7 days
C.12 days
D.24 days
Answer: D.24 days
Explanation: Explanation:
A’s 5 day work = 5*1/15=1/3
Remaining work = 1-1/3=2/3
B completes 2/3 work in 6 days
B alone can do in x days
2/3*x=16
X=24 days
Answer: Option D
Question: Which of the following CAN be the least common multiple of two positive integers 10 and 15?
A.12
B.30
C.17
D.18
Answer: B.30
Explanation: LCM of 10 & 15 is 30
Answer : B
Question: What is the compound interest paid on a sum of Rs.6000 for the period of 2 years at 10% per annum.
A.1260
B.1320
C.1200
D.1250
Answer: A.1260
Explanation: Solution= Interest % for 1st year= 10
Interest % for 2nd year= 10+ 10% of 10= 10+ 10 *10/100=11
Total % of interest= 10 + 11=21
Total interest = 21 % 6000 = 6000 * (21/100)= 1260
Answer A
Question: A train 250 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 150 m long?
A.45 sec
B.42 sec
C.32sec
D.48 sec
Answer: C.32sec
Explanation: total length= 250+150=400
speed=45km/h=(45*5)/18= 25/2m/s
time=(400*2)/25=32 sec.
ANSWER:C
Question: How many unique positive odd integers less than 100 are equal to the product of a positive multiple of 5 and an odd number?
A.4
B.10
C.11
D.12
Answer: B.10
Explanation: The Question basically asks how many positive odd integers less than 100 are odd multiples of 5
So we have 5,15,25,35,45,55,65,75,85,95
=10
Ans B
Question: In a mixed college 160 students are there in one class. Out of this 160 students 1/2 students are girls. How many boys are there ?
A.A)40
B.B)60
C.C)80
D.D)120
Answer: C.C)80
Explanation: Total Number of Students :160
Total Girls : 160*1/2=80
Total Boys : 160-80 = 80
Answer is C
Question: A sum of Rs. 1700 has been divided among A, B and C such that A gets of what B gets and B gets of what C gets. B’s share is:
A.Rs. 120
B.Rs. 160
C.Rs. 240
D.Rs. 300
Answer: D.Rs. 300
Explanation: EXPLANATION
Let C’s share = Rs. x
Then, B’s share = Rs. x/4 , A’s share = Rs. (2/3 x x/4 ) = Rs. x/6
=x/6 + x/4 + x = 1700
=> 17x/12 = 1700
=> 1700 x 12/ 17 = Rs.1200
Hence, B’s share = Rs. (1200/4) = Rs. 300.
Answer D
Question: Two employees X and Y are paid a total of Rs. 550 per week by their employer. If X is paid 120 percent of the sum paid to Y, how much is Y paid per week?
A.Rs.180
B.Rs.200
C.Rs.250
D.Rs.280
Answer: C.Rs.250
Explanation: Let the amount paid to X per week = x
and the amount paid to Y per week = y
Then x + y = 550
But x = 120% of y = 120y/100 = 12y/10
∴12y/10 + y = 550
⇒ y[12/10 + 1] = 550
⇒ 22y/10 = 550
⇒ 22y = 5500
⇒ y = 5500/22 = 500/2 = Rs.250
Option 'C'
Question: There are 9 players in a chess group, and each player plays each of the others once. Given that each game is played by two players, how many total games will be played?
A.10
B.30
C.36
D.60
Answer: C.36
Explanation: 9 players are there.
two players play one game with one another.
so 9C2=9x8/2=36
SO OPTION C is correct
Question: By selling 150 apples, a fruit-seller gains the selling price of 30 apples. Find the gain percent?
A.30%
B.58%
C.25%
D.60%
Answer: C.25%
Explanation: Option C
Explanation:
SP = CP + g
150 SP = 150 CP + 30 SP
120 SP = 150 CP
120 --- 30 CP
100 --- ? => 25%
Question: The radius of a wheel is 22.4 cm. What is the distance covered by the wheel in making 1500 resolutions?
A.2187 m
B.2112 m
C.2179 m
D.2127 m
Answer: B.2112 m
Explanation: In one resolution, the distance covered by the wheel is its own circumference. Distance covered in 1500 resolutions.
= 1500 * 2 * 22/7 * 22.4
= 211200 cm
= 2112 m
Answer:B
Question: In an election between two candidates, the first candidate got 60% of the votes and the second candidate got 480 votes. What was the total number of votes?
A.900
B.1200
C.1500
D.1800
Answer: B.1200
Explanation: Let V be the total number of votes.
0.4V = 480
V = 1200
The answer is B.
Question: Two tains of equal lengths take 10 seconds and 15 seconds respectively to cross a telegraph post. If the length of each train be 120 metres, in what time (in seconds) will they cross each other travelling in opposite direction?
A.12
B.14
C.16
D.20
Answer: A.12
Explanation: Sol.
Speed of the first train = [120 / 10] m/sec = 12 m/sec.
Speed of the second train = [120 / 15] m/sec = 8 m/sec.
Relative speed = (12 + 8) = m/sec = 20 m/sec.
∴ Required time = (120 + 120) / 20 secc = 12 sec.
Answer A
Question: A trader sells 85 meters of cloth for Rs. 8925 at the profit of Rs. 20 per metre of cloth. What is the cost price of one metre of cloth?
A.21
B.28
C.90
D.85
Answer: D.85
Explanation: Explanation:
SP of 1m of cloth = 8925/85 = Rs. 105
CP of 1m of cloth = SP of 1m of cloth - profit on 1m of cloth
= Rs. 105 - Rs. 20 = Rs. 85.
Answer: D
Question: A can run a kilometer race in 4 1/2 min while B can run same race in 5 min. How many meters start can A give B in a kilometer race, so that the race mat end in a dead heat?
A.150 m
B.125 m
C.130 m
D.100 m
Answer: D.100 m
Explanation: A can give B (5 min - 4 1/2 min) = 30 sec start.
The distance covered by B in 5 min = 1000 m.
Distance covered in 30 sec = (1000 * 30)/300 = 100 m.
A can give B 100m start.
ANSWER:D
Question: If a train, travelling at a speed of 90 kmph, crosses a pole in 5 sec, then the length of train is?
A.288
B.125
C.88
D.76
Answer: B.125
Explanation: D = 90 * 5/18 * 5 = 125 m
Answer: B
Question: 5, 7, 11, 18, 33, (...)
A.22
B.35
C.27
D.63
Answer: D.63
Explanation: Explanation :
5
5 × 2 - 3 = 7
7 × 2 - 3 = 11
11 × 2 - 3 = 18
18 × 2 - 3 = 33
33 × 2 - 3 = 63
Answer : Option D
Question: A and B can together finish a work 30 days. They worked together for 20 days and then B left. After another 20 days, A finished the remaining work. In how many days A alone can finish the work?
A.10 days.
B.30 days.
C.60 days.
D.20 days.
Answer: C.60 days.
Explanation: (A + B)'s 20 day's work =(1/30 x 20)	=2/3	.
Remaining work =(1 -2/3)=1/3.
Now,	1/3	work is done by A in 20 days.
Therefore, the whole work will be done by A in (20 x 3) = 60 days.
Answer: Option C
Question: The ratio 2:10 expressed as percent equals to
A.50 %
B.30 %
C.25 %
D.20 %
Answer: D.20 %
Explanation: Explanation:
Actually it means 2 is what percent of 10, which can be calculated as,
(2/10)*100 = 2* 10 = 20
Answer: Option D
Question: An error 2% in excess is made while measuring the side of a square. The percentage of error in the calculated area of the square is
A.4.04%
B.4.14%
C.4.23%
D.4.26%
Answer: A.4.04%
Explanation: 100 cm is read as 102 cm.
A1 = (100 x 100) cm2 and A2 (102 x 102) cm2.
(A2 - A1) = [(102)2 - (100)2]
= (102 + 100) x (102 - 100)
= 404 cm2.
Percentage error = 404	x 100	%	=
100 x 100
A)
Question: If Dinesh is 1/3rd the age of his father Kiran now, and was 1/4th the age of his father 5 years ago, then how old will his father Kiran be 5 years from now?
A.20 years
B.45 years
C.40 years
D.50 years
Answer: D.50 years
Explanation: Let the present age of Dinesh and his father be ’x’ and ’y ’respectively. Then
x = 1/3y
(x - 5) = 1/4(y - 5)
y = 45 years
Hence required age = (y + 5) = 50 years
ANSWER:D
Question: In the graduating class of a certain college, 48 percent of the students are male and 52 percent are female. In this class 40 percent of the male and 50 percent of the female students are 25 years old or older. If one student in the class is randomly selected, approximately what is the probability that he or she will be less than 25 years old?
A.A)0.9
B.B)0.5
C.C)0.45
D.D)0.3
Answer: B.B)0.5
Explanation: Percent of students who are 25 years old or older is 0.4*48+0.5*52=~45, so percent of people who are less than 25 years old is 100-45=55.
Answer: B.
Question: The average of 11 numbers is 10.9. If the average of first six is 10.5 and that of the last six is 11.4 the sixth number is?
A.11.9
B.14.2
C.11.9
D.11.5
Answer: D.11.5
Explanation: 1 to 11 = 11 * 10.9 = 119.9
1 to 6 = 6 * 10.5 = 63
6 to 11 = 6 * 11.4 = 68.4
63 + 68.4 = 131.4 – 119.9 = 11.5
6th number = 11.5
Answer:D
Question: In a contest, a bowl contains 8 keys, one of which will open a treasure chest and Seven of which will not. If a contestant selects the key that opens the treasure chest, she wins the contents of that chest. If Kiran is allowed to draw two keys, simultaneously and at random, from the bowl as the first contestant, what is the probability that he wins the prize?
A.1/4
B.1/2
C.1/3
D.1/5
Answer: A.1/4
Explanation: The total possibilities existing while withdrawing two keys are: 8C2 = 28
For Kiran to win, 7 combinations exist assuming Key 1 to unlock the treasure E.g(1,2), (1,3)....(1,7)
P = 7/28= 1/4
Option A
Question: Convert the 15/36 m/s into kilometers per hour?
A.3.5 kmph.
B.2.5 kmph.
C.1.2 kmph.
D.1.5 kmph.
Answer: D.1.5 kmph.
Explanation: 15/36 m/s = 13/36 * 18/5 = 15/10 = 1.5 kmph.
ANSWER:D
Question: If xerox paper costs 5 cents a sheet and a buyer gets 10% discount on all xerox paper one buys after the first 2000 papers and 20% discount after first 10000 papers, how much will it cost to buy 35000 sheets of xerox paper?
A.$1250
B.$1060
C.$1450
D.$900
Answer: C.$1450
Explanation: 30 sec approach - solve it using approximation
35000 sheet at full price, 5 cent = 1750
35000 sheet at max discount price, 4 cent = 1400
Your ans got to be between these two.
Ans C it is.
Question: The price of lunch for 13 people was $207 including a 15% gratuity for service. What was the average price per person, EXCLUDING the gratuity?
A.11.73
B.12
C.13.85
D.14
Answer: C.13.85
Explanation: Clearly C is the answer
I used POE here
Lets consider option (C)
13*13.85= 180 now 180(115/100)=207
=> possible ANSWER IMO C
Question: The daytime telephone rate between two cities is 50 cents for the first 3 minutes and c cents for each additional minute. The total charge is reduced 60 percent on calls made after 10:00 P.M. The cost, in dollars, of a 35-minute call made at 10:30 P.M. between these two cities is:
A. 0.4(0.60) + 35c
B. 0.4(0.50 + 0.32c)
C. 0.4(0.60 + 9c)
D. 0.6(0.60 + 32c)
Answer: B. 0.4(0.50 + 0.32c)
Explanation: For first three minutes = 50 cents
Remaining minutes = 35 -3 = 32
charge for 32 minutes = 32c
total cost (if the call was made in daytime) = 0.50 + 32c
60% chargereducedon night calls => 40% charge
=>0.4(0.50 + 32c)
Hence, Answer is B
Question: In Kiran's opinion, his weight is greater than 65 kg but less than 72 kg. His brother does not agree with Kiran and he thinks that Kiran's weight is greater than 60 kg but less than 70 kg. His mother's view is that his weight cannot be greater than 68 kg. If all are them are correct in their estimation, what is the average of different probable weights of Kiran?
A.67
B.68
C.69
D.70
Answer: A.67
Explanation: Let Kiran's weight = x. Then
According to Kiran, 65 < x < 72 ----(equation 1)
According to brother, 60 < x < 70 ----(equation 2)
According to mother, x ≤ 68 ----(equation 3)
Given that equation 1,equation 2 and equation 3 are correct. By combining these equations,we can write as
65<x≤68
i.e., x = 66 or 67 or 68
Average of different probable weights of Kiran = (66+67+68)/3=67
Answer is A.
Question: X and Y invest Rs.21000 and Rs.17500 respectively in a business. At the end of the year, they make a profit of Rs.26400. What is the share of X in the profit?
A.14400
B.26400
C.12000
D.12500
Answer: A.14400
Explanation: Explanation:
Ratio of the investment
=21000:17500=210:175
=42:35=6:5
Share of X in the profit
=2400 x 6/11
=2400×6=14400
Answer: Option A
Question: Working together, printer A and printer B would finish the task in 24 minutes. Printer A alone would finish the task in 60 minutes. How many pages does the task contain if printer B prints 10 pages a minute more than printer A ?
A.600
B.800
C.1000
D.1200
Answer: D.1200
Explanation: Answer: D.
Question: Find the roots of quadratic equation: 2x2 + 5x + 2 = 0?
A.-2, -1/2
B.4, -1
C.4, 1
D.-2, 5/2
Answer: A.-2, -1/2
Explanation: 2x2 + 4x + x + 2 = 0
2x(x + 2) + 1(x + 2) = 0
(x + 2)(2x + 1) = 0 => x = -2, -1/2
ANSWER:A
Question: The difference between a positive proper fraction and its reciprocal is 9/20. The fraction is:
A.3/5
B.3/10
C.4/5
D.5/4
Answer: C.4/5
Explanation: Let the required fraction be x. Then,
1/x - x = 9/20
20x2 + 9x - 20 = 0
20x2 + 25x - 16x - 20 = 0
5x(4x + 5) -4(4x + 5) = 0
(4x + 5)(5x - 4) = 0
x = 4/5
ANSWER:C
Question: What percent of 60 is 80?
A.133 1⁄3
B.75
C.60
D.33 1⁄3
Answer: A.133 1⁄3
Explanation: % of 60 is 80?
= 80/60 = 4/3 = 133.33%
Thus A is the correct answer.
Question: A can do a piece of work in 30 days. He works at it for 5 days and then B finishes it in 20 days. In what time can A and B together it?
A.13 1/8 days
B.13 1/3 days
C.83 1/3 days
D.13 8/3 days
Answer: B.13 1/3 days
Explanation: 5/30 + 20/x = 1
x = 24
1/30 + 1/24 = 3/40
40/3 = 13 1/3 days
Answer: B
Question: Some man have some apples with him.He gave half of the apples and half an apple.This gets repeated for 4 time.After that he has no more apple with him.How many number of apples were there initially?
A.30
B.31
C.32
D.33
Answer: C.32
Explanation: some apples=x
he gave half of an apples and half of an apple and reaming he have are x/2-1/2
It is repeated four times
2nd time x/4-1/2-1/2
3d time x/8-1/2-1/2-1/2
4th time x/16-1/2-1/2-1/2-1/2=0
x/16-2=0
x=32
ANSWER:C
Question: If the cost price of 50 articles is equal to the selling price of 30 articles, then the gain or loss percent is?
A.22
B.65
C.78
D.66.67
Answer: D.66.67
Explanation: Given that, cost price of 50 article is equal to selling price of 30 articles.
Let cost price of one article = Rs. 1
Selling price of 30 articles = Rs. 50
But Cost price of 30 articles = Rs. 30
Therefore, the trader made profit.\Percentage of profit = 20/30 * 100 = 66.67%
Answer:D
Question: Pumps A, B, and C operate at their respective constant rates. Pumps A and B, operating simultaneously, can fill a certain tank in 1 hours; pumps A and C, operating simultaneously, can fill the tank in 1 hours; and pumps B and C, operating simultaneously, can fill the tank in 2 hours. How many hours does it take pumps A, B, and C, operating simultaneously, to fill the tank.
A.1/3
B.1/2
C.1/4
D.1
Answer: B.1/2
Explanation: A+B =1 ; A+C =1 ,B+C =2 ; ADD THEN 2*(A+B+C) = 4
A+B+C = 2 HRS
B
Question: Kira's seafood restaurant gets a delivery of fresh seafood every day, 7 days per week, and her delivery company charges her dollars per delivery plus cents per item delivered. If lst week Sarah's seafood restaurant had an average of x items per day delivered, then which of the following is the total cost, in dollars, of last week's deliveries ?
A.7cdx/100
B.d + 7cx/100
C.7d + xc/100
D.7d + 7xc/100
Answer: D.7d + 7xc/100
Explanation: Answer is D.
Question: Torry has submitted 2/5 of his homework assignments, and he received an average grade of 75 for those assignments. If he wishes to receive an average grade of 120 for all his homework assignments, the average grade for Torry's remaining homework assignments must be what percent greater than the average grade for the assignments he has already submitted?
A.100%
B.20%
C.25%
D.33 1/3%
Answer: A.100%
Explanation: 0.4*75 + 0.6x = 120
30 + 0.6x=120
0.6x = 90
x= 150
150/75=2
Ans:A
Question: The average of 15 result is 60. Average of the first 10 of them is 10 and that of the last 10 is 80. Find the 8th result?
A.35
B.200
C.150
D.250
Answer: B.200
Explanation: Sum of all the 13 results = 15 * 60 = 900
Sum of the first 7 of them = 10 * 10 = 100
Sum of the last 7 of them = 10 * 80 = 800
So, the 8th number = 900 + 100 - 800 = 200.
B
Question: Lilly has 10 fish and Rosy has 11 fish. In total, how many fish do they have in all?
A.19
B.20
C.21
D.22
Answer: C.21
Explanation: 10+11=21
The answer is C.
Question: Ten years ago, P was half of Q's age. If the ratio of their present ages is
3:4, what will be the total of their present ages?
A.45
B.40
C.35
D.30
Answer: C.35
Explanation: Let present age P and Q be 3x 4x respectively
Ten years ago, P was half of Q's age
(3x-10) = 1/2 (4x-10)
2x = 10
x=5
Total of their present ages = 3x+4x = 7x = 7 * 5 = 35
ANSWER C
Question: The effective annual rate of interest corresponding to a nominal rate of 12% per annum payable half-yearly is?
A.16.06%
B.16.07%
C.12.36%
D.6.09%
Answer: C.12.36%
Explanation: Amount of Rs. 100 for 1 year when compounded half-yearly = [100 * (1 + 6/100)2] = Rs. 112.36 Effective rate = (112.36 - 100) = 12.36%
ANSWER:C
Question: The percentage increase in the area of a rectangle, if each of its sides is increased by 20% is
A.38%
B.40%
C.44%
D.48%
Answer: C.44%
Explanation: Let original length = x metres and original breadth = y metres.
Original area = (xy) m2.
New length = 120 x m = 6 x m.
100 5
New breadth = 120 y m = 6 y m.
100 5
New Area = 6 x x 6 y m2 = 36 xy m2.
5 5 25
The difference between the original area = xy and new-area 36/25 xy is
= (36/25)xy - xy
= xy(36/25 - 1)
= xy(11/25) or (11/25)xy
Increase % = 11 xy x 1 x 100 % = 44%.
25 xy
C)
Question: The average (arithmetic mean) of the even integers from 0 to 40 inclusive is how much greater than the average (arithmetic mean) of the even integers from 0 to 20 inclusive?
A.10
B.20
C.5
D.30
Answer: A.10
Explanation: So, according to A mean of a set of even numbers from 0 to 40 =(0+40)/2=20 and mean of a set of even numbers from 0 to 20 =(0+20)/2=10
Difference=20-10=10
Answer: A.
Question: A can do a piece of work in 4 hours; B and C together can do it in 3 hours, which A and C together can do it in 2 hours. How long will B alone take to do it?
A.15 hours
B.14 hours
C.12 hours
D.74 hours
Answer: C.12 hours
Explanation: A's 1 hour work = 1/4;
(B + C)'s 1 hour work = 1/3;
(A + C)'s 1 hour work = 1/2
(A + B + C)'s 1 hour work = (1/4 + 1/3) = 7/12
B's 1 hour work = (7/12 + 1/2) = 1/12
B alone will take 12 hours to do the work.
Answer:C
Question: A tyre has two punctures. The first puncture alone would have made the tyre flat in 9 minutes and the second alone would have done it in 4 minutes. If air leaks out at a constant rate, how long does it take both the punctures together to make it flat ?
A.3 1/5min
B.2 10/13min
C.3 3/5min
D.3 4/5min
Answer: B.2 10/13min
Explanation: Explanation:
Do not be confused, Take this question same as that of work done question's. Like work done by 1st puncture in 1 minute and by second in 1 minute.
Lets Solve it:
1 minute work done by both the punctures =
(1/9+1/4)=(13/36)
So both punctures will make the type flat in
(36/13)mins=2 10/13mins
Option B
Question: A man can swim in still water at 9 km/h, but takes twice as long to swim upstream than downstream. The speed of the stream is?
A.1.7
B.1.4
C.3
D.1.5
Answer: C.3
Explanation: M = 9
S = x
DS = 9+ x
US = 9 + x
9 + x = (9 - x)2
9+ x = 18 -2x
3x = 9
x = 3
Answer:C
Question: If 5x^2 has two different prime factors, at most how many different prime factors does x have?
A.1
B.2
C.3
D.4
Answer: B.2
Explanation: x cannot have more than 2 prime factors, because in this case 5x^2 would also have more than 2 prime factors.
Can x have 2 prime factors? Yes, consider x=2*5=10 (in this case 5x^2 still has 2 prime factors).
Answer: B.
Question: A person bought a certain quantity of rice at the rate of Rs. 150/quintal. 10% of the rice was spoiled. At what rate(per quintal) should he sell the remaining rice to earn 20% profit.
A.Rs. 180
B.Rs. 200
C.Rs. 210
D.Rs. 220
Answer: B.Rs. 200
Explanation: Solution: Suppose he buy 1 quintal of Rice in Rs.150.
10% is spoiled so he now have to sell of 90 kg remaining)
.But he has to make a profit of 20%,so he will sell
90kg for Rs. 180
This means his selling price is Rs. 200 per quintal.
Answer: Option B
Question: By selling an article at Rs.800, a shopkeeper makes a profit of 25%. At what price should he sell the article so as to make a loss of 30%?
A.448
B.480
C.267
D.288
Answer: A.448
Explanation: SP = 800
Profit = 25%
CP = (SP)*[100/(100+P)]
= 800 * [100/125]
= 640
Loss = 25% = 25% of 640 = Rs.192
SP = CP - Loss = 640 - 192 = Rs.448
Answer: A
Question: If 7log(4*5^2) = x, find x
A.12
B.11
C.10
D.14
Answer: D.14
Explanation: 7(log2^2*5^2)=x
7log(5*2)^2=x
7*2log(5*2)=x
14log10=x
log10 base 10=1
so
14*1=x
x=14
ANSWER:D
Question: There is 2/5 chance it will rain today.
There is a probability of 1/2 I will find the love of my life today.
What is the probability I will find the love of my life in the rain today?
A.2/5
B.3/5
C.3/10
D.1/5
Answer: D.1/5
Explanation: In order to find the answer we need to multiply the probabilities - 2/5*1/2=1/5
Answer:D
Question: A particular library has 75 books in a special collection, all of which were in the library at the beginning of the month. These book are occasionally loaned out through an inter-library program. If, by the end of the month, 65 percent of books that were loaned out are returned and there are 61 books in the special collection at that time, how many books of the special collection were loaned out during that month?
A.20
B.30
C.35
D.40
Answer: D.40
Explanation: The total number of books is 75.
Let x be the number of books which were loaned out.
65% of books that were loaned out are returned.
35% of books that were loaned out are NOT returned.
Now, there are 61 books, thus the number of un-returned books is 75-61 = 14 books.
0.35x = 14
x = 40
The answer is D.
Question: The distance from City A to City B is 180 miles. While driving from City A to City B, Cara drives at a constant speed of 30 miles per hour. Dan leaves City A 60 minutes after Cara. What is the minimum constant speed in miles per hour that Dan must exceed in order to arrive in City B before Cara?
A.42
B.44
C.46
D.36
Answer: D.36
Explanation: The time it takes Cara to drive to City B is 180 / 30 = 6 hours.
Dan needs to take less than 5 hours for the trip.
Dan needs to exceed a constant speed of 180 / 5 = 36 miles per hour.
The answer is D.
Question: At a school dance, 40% of the students had a date, 70% of the remaining students arrived at the dance with a group. What percentage of the students arrived alone?
A.40% of the students arrived alone.
B.10% of the students arrived alone.
C.42% of the students arrived alone.
D.18% of the students arrived alone.
Answer: D.18% of the students arrived alone.
Explanation: Explanation:Let total number of students be 100,Then, number of students with a date = 40.Number of students arriving with a group= 70% of 60 = 42.Total number of students arriving alone = 100 – (40 + 42) = 18.Thus, 18% of the students are arriving alone.Answer: Option D.
Question: With both inlets open, a water tank will be filled with water in 24 minutes. The first inlet alone would fill the tank in 2 hours. If in every minutes the second inlet admits 50 cubic meters of water than the first, what is the capacity of the tank ?
A.2,000
B.10,500
C.11,750
D.12,000
Answer: A.2,000
Explanation: The work Done by Inlet A and B together in 1 min = 1/24
The work Done by Inlet A (First Inlet) in 1 min = 1/120
The work Done by Inlet B (Second Inlet) in 1 min = (1/24)- (1/120) = 1/30
DIfference of Work done by B and A = B - A = 50 Cubic meter
i.e. (1/30)- (1/120) = 50 Cubic meter
i.e. Tank = 40*50 = 2000 Cubic Meter
Answer: option A
Question: By selling 8 pencils for a rupee a man loses 10%. How many for a rupee should he sell in order to gain 10%?
A.6.54
B.9.45
C.7.34
D.6.67
Answer: A.6.54
Explanation: 90% --- 8
110% --- ?
90/110 * 8 = 6.54
Answer: A