RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: There are 100 freshmen at a particular college, all of whom must take at least one of the three core classes: Art, Biology, and Calculus. Of these freshmen, 17 take only Biology, 6 take only Calculus, 5 take all three classes, and 20 take Art and exactly one of the other two core classes. If the number of freshmen who take only Art is 3 times the number of freshmen who take every core class except Art, how many freshmen take Art?
A.64
B.32
C.36
D.48
Answer: A.64
Explanation: Make a venn diagram to get a clear picture. Look at the diagram:
Each letter represents only one color. b represents the people who take only Art. d represents people who take only Art and Bio etc.
d + f = 20 (People who take Art and one other class)
b = 3e (people who take only Art is 3 times the people who take Bio and Calculus)
17 + 6 + 5 + b + d + e + f = 100 (Total people)
b + b/3 = 52
b = 39
Number of freshmen who take Art = 39 + 20 + 5 = 64
Answer A
Question: A train speeds past a pole in 15 seconds and a platform 100 m long in 25 seconds. Its length is?
A.287 m
B.287 m
C.288 m
D.150 m
Answer: D.150 m
Explanation: Let the length of the train be x meters and its speed be y m/sec.
They, x / y = 15 => y = x/15
x + 100 / 25 = x / 15
x = 150 m.
Answer:D
Question: If The GCD of two numbers (not equal, both integers, greater than 1) is 2, then which of the following can be true?
A. They are prime.
B. They are even.
C. They do not have a common prime factor.
D. They do not have a common factor other than 2.
A.Only A
B.Only B
C.Only C
D.Only D
Answer: B.Only B
Explanation: The GCD of two numbers (not equal, both integers, greater than 1) is 2 means that they don't share factors other than 1 and 2.
This also means that both numbers are even ( divisible by 2.)
A. They are not prime. 2 is the only even number that is prime, so one number can be prime but the other number cannot be.
B. They are even. Since they are divisible by 2, they are even..
C. They have a common prime factor. The question defines the numbers as having a GCD of 2, which is prime.
D. They have a common factor other than 2. Both numbers have common factors of 2 and 1. For example:
The factors of 4 are 1 and 2, the factors of 6 are 1, 2, and 3.
Therefore, (B) is the only correct answer.
Question: X can do a piece of work in 15 days. If he is joined by Y who is 50% more efficient, in what time will X and Y together finish the work?
A.10 days
B.6 days
C.18 days
D.Data insufficient
Answer: B.6 days
Explanation: X’s one day’s work = 1⁄15 th work.
Y’s one day’s work = 1⁄15 + 50% of 1⁄15 = 1⁄10 th work.
∴ (X + Y)’s one day’s work = 1⁄15 + 1⁄10 = 1⁄6 th work.
Hence, they together finish the work in 6 days.
Answer B
Question: A company seeks to hire a sales manager, a shipping clerk, and a receptionist. The company has narrowed its candidate search and plans to interview all remaining candidates including 6 persons for the position of sales manager, 4 persons for the position of shipping clerk, and 10 persons for the position of receptionist. How many different hiring of these three people are possible?
A.6 + 4 + 10
B.6 × 4 × 10
C.21 × 20 × 19
D.6! + 4! + 10!
Answer: B.6 × 4 × 10
Explanation: 1 sales manager can be selected out of 6 in 6 ways
1 clerk can be selected out of 4 in 4 ways
1 receptionist can be selected out of 10 in 10 ways
total no. of ways these 3 can be selected = 6 *4 * 10
Ans. B) 6 × 4 × 10
Question: A father left a will of 68,000 to be divided between his two sons aged 10 years and 12 years such that they may get equal amount when each attains the age of 18 years If the money is reckoned at 10% p.a., find how much each gets at the time of the will.
A.30,000, 38,000
B.28,000, 40,000
C.32,000, 36,000
D.Cannot be determined.
Answer: C.32,000, 36,000
Explanation: Let one gets = x
then, second gets = (68,000 – x)
Given : A1 = A2
x+x×10×8/100=(68,000−x)+(68,000−x)×10×6/100
⇒ x[100 + 80] = (68,000 - x)[100 + 60]
⇒ 180⁄160x = 68,000 - x
⇒ 34x = 68000 × 16 ⇒ x = 32000
∴ second gets = 36,000
Answer C
Question: The average weight of 8 people increases by 2.5 kg when a new person comes in place of one of them weighing 55 kg. What is the weight of the new person?
A.75 kg
B.85 kg
C.95 kg
D.65 kg
Answer: A.75 kg
Explanation: The total weight increase = (8 x 2.5) kg = 20 kg
weight of new person = (55 + 20) kg = 75 kg
The answer is A.
Question: If a - b = 3 and a^2 + b^2 = 35, find the value of ab.
A.12
B.13
C.10
D.18
Answer: B.13
Explanation: 2ab = (a^2 + b^2) - (a - b)^2
= 35 - 9 = 26
ab = 13.
Answer is B.
Question: A train running at the speed of 60 km/hr crosses a pole in 9 seconds. What is the length of the train?
A.227
B.277
C.272
D.150
Answer: D.150
Explanation: Speed=(60 * 5/18) m/sec = (50/3) m/sec Length of the train = (Speed x Time) = (50/3 * 9) m = 150 m.
Answer: D
Question: In a lottery, there are 10 prizes and 25 blanks. A lottery is drawn at random. What is the probability of getting a prize?
A.1/10
B.2/5
C.2/7
D.5/7
Answer: C.2/7
Explanation: Explanation:
P (getting a prize) =	10/(10 + 25)	=	10/35	= 2/7.
ANSWER : C
Question: Two trains A and B are 125 m and 150 m long and are moving at one another at 54 Km/hr and 36 Km/hr respectively. Arun is sitting on coach B1 of train A. Calculate the time taken by Arun to completely cross Train B.
A.10 s
B.11 s
C.4 s
D.8 s
Answer: B.11 s
Explanation: DETAILED SOLUTION
Speed of A = 54∗1000/60∗60 = 15 m/s
Speed of B = 36∗1000/60∗60 = 10 m/s
Relative speed = S1 + S2 = 15 + 10 m/s = 25 m/s
The length that needs to be crossed = length of train B = 150 m. Therefore time taken = 150/25 = 6s.
What is the time taken for trains to completely cross each other? The length that needs to be crossed = 125 + 150 = 275 m. Time taken = 275/25 = 11 s.
CORRECT ANSWER B.
Question: A 270 m long train running at the speed of 120 km/hr crosses another train running in opposite direction at the speed of 80 km/hr in 9 sec. What is the length of the other train?
A.230
B.277
C.299
D.267
Answer: A.230
Explanation: Relative speed = 120 + 80 = 200 km/hr.
= 200 * 5/18 = 500/9 m/sec.
Let the length of the other train be x m.
Then, (x + 270)/9 = 500/9 => x = 230.Answer:A
Question: If the side length of Square B is five times that of Square A, the area of Square B is how many times the area of Square A?
A.5
B.15
C.25
D.35
Answer: C.25
Explanation: Let x be the side length of Square A.
Then the area of Square A is x^2.
The area of Square B is (5x)^2=25x^2.
The answer is C.
Question: A box contains 3 blue marbles, 4 red, 6 green marbles and 2 yellow marbles. If four marbles are picked at random, what is the probability that none is blue?
A.33/95
B.33/91
C.33/99
D.33/96
Answer: B.33/91
Explanation: Given that there are three blue marbles, four red marbles, six green marbles and two yellow marbles. When four marbles are picked at random, then the probability that none is blue is
= 12C4/15C4
= (12 * 11 * 10 * 9)/(15 * 14 * 13 * 12) = 33/91
Answer: B
Question: The ratio of the number of ladies to gents at a party was 1:2 but when 2 ladies and 2 gents left, the ratio became 1:3. How many people were at the party originally?
A.44
B.11
C.12
D.98
Answer: C.12
Explanation: x, 2x
(x-2):(2x-2) = 1:3
3x-6 = 2x-2
x = 4
x+2x = 3x
=> 3*4 = 12
Answer: C
Question: Sum of 3 consecutive even no.'s is 30 more than the 1st no. of the series. Find the middle no.?
A.8
B.12
C.14
D.16
Answer: C.14
Explanation: Let the numbers be x, x+2 and x+4 then
x + x+2 + x+4 = x+30
3x + 6 = x + 30
2x = 24
\inline \therefore x = 12
\inline \therefore Middle number = x + 2 = 12+2 = 14
C
Question: An investment yields an interest payment of $228 each month. If the simple annual interest rate is 9%, what is the amount of the investment?
A.$28,300
B.$30,400
C.$31,300
D.$32,500
Answer: B.$30,400
Explanation: Let the principal amount = P
Simple annual interest = 9%
Simple monthly interest = (9/12) = (3/4)%
(3/4)*(P/100) = 228
=>P = (228 *4 * 10^2 )/3
= 76*4*10^2
= 304 * 10^2
Answer B
Question: The average age of the boys in a class is 16 years and that of the girls is 15 years. The average age for the whole class is
A.18
B.67
C.02
D.Data inadequate
Answer: D.Data inadequate
Explanation: Explanation:
Clearly, to find the average, we ought to know the number of boys, girls or students in the class, neither of which has been given.
So, the data provided is inadequate.
Answer: D
Question: A certain electric-company plan offers customers reduced rates for electricity used between 8 p.m. and 8 a.m. weekdays and 24 hours a day Saturdays and Sundays. Under this plan, the reduced rates W apply to what fraction of a week?
A. 1/2
B. 5/8
C. 9/14
D. 16/21
Answer: C. 9/14
Explanation: Number of hours between 8 PM to 8 AM = 12
Number of hours with reduced rates = (12*5)+(24*2)
Hours with reduced rates W/Total number of hours in a week = (12*5)+(24*2)/(24*7) = 108/(24*7) = 9/14
Answer: C
Question: If 10 toys cost Rs, 234, what do 35 toys cost?
A.645
B.564
C.546
D.819
Answer: D.819
Explanation: Let the required cost be Rs. x. Then,
More toys, More cost	(Direct Proportion)
x=(35 X 234)/10 =819
Answer is D
Question: What is the greatest positive integer n such that 3^n is a factor of 54^100?
A.100
B.200
C.300
D.600
Answer: C.300
Explanation: 54 = 3^3 * 2.
54^100 = 3^300 * 2^100
The answer is C.
Question: How many odd integers F between 200 and 600 are there such that their tens digit is even?
A.20
B.25
C.100
D.150
Answer: C.100
Explanation: The hundreds digit can take 4 values: 2, 3, 4 and 5;
The tens digit can take 5 values: 0, 2, 4, 6 and 8;
The units digit can take 5 values: 1, 3, 5, 7 and 9;
Total F: 4*5*5=100.
Answer: C.
Question: In the presidential election, 55% of the people who voted, voted for the democratic candidate and 35% voted for the republican candidate. If 8% of the number of people eligible to vote, voted for neither the republican nor the democrat, what percent of people eligible to vote actually voted in the elections?
A.40
B.60
C.80
D.88
Answer: C.80
Explanation: let people eligible to vote = y
people actually voted = x
Democratic = 0.55x
Republican = 0.35 x
total voters = 0.90 x
hence 0.10x voters who voted didnt voted for D and R.
now, 0.10 x = 0.08 y
=> x/y = 8/10
hence 80%
Hence C
Question: If Sharon's weekly salary increased by 15 percent, she would earn $460 per week. If instead, her weekly salary were to increase by 10 percent, how much would she earn per week?
A.Rs.400
B.Rs.440
C.Rs.150
D.Rs.460
Answer: B.Rs.440
Explanation: Soln:-
460/115)110 =385
In this case long division does not take much time.
(4/1)110=Rs.440
ANSWER:B
Question: In a certain village, n litres of water are required per household per month. At this rate, if there are m households in the village, how long (in months) will p litres of water last?
A.p /m
B.P/mn
C.mp / n
D.np / m
Answer: B.P/mn
Explanation: I find it much easier to understand with real numbers, so choose (almost) any numbers to replace m,n and p:
(p/m*n)
Answer (B)
Question: Rs.1500 is divided into two parts such that if one part is invested at 6% and the other at 5% the whole annual interest from both the sum is Rs.85. How much was lent at 5%?
A.399
B.700
C.288
D.500
Answer: D.500
Explanation: (x*5*1)/100 + [(1500 - x)*6*1]/100 = 85
5x/100 + 90 – 6x/100 = 85
x/100 = 5
=> x = 500
Answer: D
Question: A city has a population of 3,00,000 out of which 1,80,000 are males. 50% of the population is literate. If 70% of the males are literate, the number of literate females is :
A.20,000
B.24,000
C.30,000
D.34,000
Answer: B.24,000
Explanation: population - 3,00,000,
males -1,80,000,
females-1,20,000
50% of 3,00,000 literate - so 1,50,000 literate
70% of 1,80,000 literate -so 1,26,000 male literates , so rest s
1,50,000 - 1,26,000 = 24,000
ANSWER:B
Question: If you write down all the numbers from 1 to 100, then how many times do you write 3 ?
A.11
B.18
C.20
D.21
Answer: C.20
Explanation: Explanation:
Explanation:
Clearly, from 1 to 100, there are ten numbers with 3 as the unit's digit- 3, 13, 23, 33, 43, 53, 63, 73, 83, 93; and ten numbers with 3 as the ten's digit - 30, 31, 32, 33, 34, 35, 36, 37, 38, 39.
So, required number = 10 + 10 = 20.
Answer: C
Question: The arithmetic mean of the scores of a group of students in a test was 42. The brightest 20% of them secured a mean score of 80 and the dullest 25% a mean score of 31. The mean score of remaining 55% is?
A.A)61.4.
B.B)51.7
C.C)33.18
D.D)51.1
Answer: C.C)33.18
Explanation: Let the required mean score be x. Then,
20 * 80 + 25 * 31 + 55 * x = 42 * 100
= 1600 + 775 + 55x = 4200
= 55x = 1825
= x = 33.18
Answer:C
Question: Murali travelled from city A to city B at a speed of 40 kmph and from city B to city C at 60 kmph. What is the average speed of Murali from A to C given that the ratio of distances between A to B and B to C is 1 : 2?
A. 48 kmph
A.33
B.360/7
C.28
D.27/8
Answer: B.360/7
Explanation: Let the distances between city A to B and B to C be x km and 2x km respectively.
Total time taken to cover from A to C
= (x)/40 + (2x)/60 = (3x + 4x)/120 = 7x/120 Average speed = (x + 2x)/(7x/120) = 360/7 kmph.
Answer: B
Question: If 22 men do a work in 55 days, in how many days will 10 men do it?
A.121
B.123
C.119
D.125
Answer: A.121
Explanation: 22 * 55 = 10 * x
x = 121 days
Answer: A
Question: 2 years ago, the average age of a family of 5 members was 16 years. After a baby is born, the average age of family is the same today. Find the present age of the baby.
A.4 years
B.6 years
C.8 years
D.8 ½ years
Answer: B.6 years
Explanation: Hint: (1) First find total age of 5 members 2 years ago (2) Present age of 5 members (3) Total age of 6 members (4) Age of baby = Total age of 6 members - Present age of 5 members
We know that,
Average =Sum of Quantities / Number of Quantities
1) First calculate total age of 5 members 2 years ago = (Average age of 5 members x number of members)
First calculate total age of 5 members 2 years ago = (16 x 5) = 80 years
2) Calculate the present age of 5 members
2 years ago, their total age was 80 years. Present age can be calculated as follows:
Present age of 5 members = [80 + (2 x 5)] = 90 years
3) Calculate total age of 6 members considering baby = (16 x 6 ) = 96 years
4) Age of baby = (96 – 90) = 6 years
ANSWER IS B
Question: A certain sum of money at simple interest amounted Rs.840 in 10 years at 3% per annum, find the sum?
A.287
B.276
C.279
D.646
Answer: D.646
Explanation: 840 = P [1 + (10*3)/100]
P = 646
Answer: D
Question: The cost of 10 kg of mangos is equal to the cost of 24 kg of rice. The cost of 6 kg of flour equals the cost of 2 kg of rice. The cost of each kg of flour is $25. Find the total cost of 4 kg of mangos, 3 kg of rice and 5 kg of flour?
A.347
B.987
C.1070
D.1371
Answer: C.1070
Explanation: Let the costs of each kg of mangos and each kg of rice be $a and $r respectively.
10a = 24r and 6 * 25 = 2r
a = 12/5 r and r = 75
a = 180
Required total cost = 4 * 180 + 3 * 75 + 5 * 25
= 720 + 225 + 125 = $1070
C
Question: Seven years back, a father was 48 years older than his son. At present the father is 4 times as old as the son. How old will the son be three years from now?
A.16 years
B.17 years
C.18 years
D.19 years
Answer: D.19 years
Explanation: Using linear equations to convert the word problem:
** F = fathers current ageS = sons current age
#1 Seven years back, a father was 48 years older than his son: F-7 = 48 + (S - 7)
#2 At present the father is 4 times as old as the son: F = 4*S
How old will the son be three years from now?: S + 3 = ?
With two variables and two linear equations we are able to solve the problem:
(S*4) - 7 = 48 +S -7
3S=48
S = 16
S + 3 = 16 + 3 = 19
Answer: D
Question: Peeta asks Katniss, 'It is 10 9m as per my watch right now.Do you know what will be the time 23, 999, 996 hours later?'
Katniss knows the answer. Do you ?
A.5pm
B.6pm
C.4am
D.7pm
Answer: D.7pm
Explanation: D
7pm
The time after 24, 000, 000 hours will be the same as it is now. We want the time 3 hours before that and thus you can deduct three hours from 9 pm. So the time will be 6 pm.
Question: How many multiples of 7 are there between 700 and 1000, inclusive?
A.43
B.42
C.22
D.21
Answer: A.43
Explanation: There are exactly 301 numbers between 700 to 1000..
701 to 800 = 100
801 to 1000 = 200...Total 300 numbers , count 700 too..
301/7 = 43...
Ans option A.
Question: The average weight of 8 person’s increases by 2.5 kg when a new person comes in place of one of them weighing 65 kg. What might be the weight of the new person?
A.75 kg
B.85 kg
C.95 kg
D.65 kg
Answer: B.85 kg
Explanation: Explanation:
Total weight increased = (8 x 2.5) kg = 20 kg.
Weight of new person = (65 + 20) kg = 85 kg.
Answer B
Question: A man has 1044 candles. After burning, he can make a new candle from 9 stubs left behind. Find the maximum number of candles that can be made.
A.116
B.120
C.130
D.140
Answer: C.130
Explanation: Explanation :
Since, 1 candle is made from 9 stubs.
Therefore, from 1044 stubs, 1044/9 i.e 116 candles will be made.
Now, from 116 stubs, 116/9 i.e 12 candles can be made and 8 stubs will be left.
Thus, total stubs left is (12+8) = 20 out of which 20/9 i.e 2 candles can be made and 2 stubs will be left.
Thus, maximum number of candles that can be made is 130 (116+12+2).
Answer : C
Question: Mary, Peter, and Lucy were picking chestnuts. Mary picked twice as much chestnuts than Peter. Lucy picked 5 kg more than Peter. Together the three of them picked 29 kg of chestnuts. How many kilograms of chestnuts did Mary, Peter, and Lucy pick respectively?
A.6, 11 and 12
B.12, 11 and 6
C.11, 6 and 12
D.12, 6 and 11
Answer: D.12, 6 and 11
Explanation: M = 2P
L = P+5
M + P + L = 29
2P + P + (P+5) = 29
P = 6, M = 12, L = 11
Therefore, Mary, Peter, and Lucy picked 12, 6, and 11 kg, respectively.
The answer is D.
Question: A train covers a distance in 50 min, if it runs at a speed of 48kmph on an average. The speed at which the train must run to reduce the time of journey to 10min will be.
A.60 km/h
B.55 km/h
C.240 km/h
D.70 km/h
Answer: C.240 km/h
Explanation: Time=50/60 hr=5/6hr
Speed=48mph
distance=S*T=48*5/6=40km
time=10/60hr=1/6hr
New speed = 40* 6/1 kmph= 240kmph
Answer : C
Question: Company P had 15 percent more employees in December than it had in January. If Company P had 450 employees in December, how many employees did it have in January?
A. 391
B. 392
C. 410
D. 423
Answer: B. 392
Explanation: D = number of employees in December
J = number of employees in January
J x 1.15 = D
J x 1.15 = 450
J = 450/1.15
J = 45,000/115 = 392
Thus B is the correct answer.
Question: Sum of 3 consecutive even no.'s is 26 more than the 1st no. of the series. Find the middle no.?
A.10
B.12
C.14
D.18
Answer: B.12
Explanation: Let the numbers be x, x+2 and x+4 then
x + x+2 + x+4 = x+26
3x + 6 = x + 26
2x = 20
\inline \therefore x = 10
\inline \therefore Middle number = x + 2 = 10+2 = 12
B
Question: Anand starts from a point P towards point Q, where PQ = 80 km. After 1 hour, Ram starts from P and catches up with Anand after 2 more hours. After meeting they continue to travel towards Q. On reaching Q, Ram reverses his direction and meets Anand 6 hours after the first meeting. Find Anand's speed.
A.(45/7) kmph
B.(160/21) kmph
C.(40/7) kmph
D.(30/7) kmph
Answer: B.(160/21) kmph
Explanation: Let the first meeting point be at a distance of x km from P, the remaining distance until Q would be (80-x) km
Anand traveled this x kms in 3 hours, making his speed x/3 kmph
Ram traveled the same x kms in 2 hours, making his speed x/2 kmph
So, in 6 hours:
Anand will cover=6x/3=2x km
Ram will cover=6x/2=3x km
And between their first meeting point and second, they both together covered a distance of 2(90-x) km.
2x+3x=2(80-x)
5x=160-2x
7x=160
x=160/7 km
Anand's speed=x/3=160/(3*7)=160/21 kmph
Ans:B
Question: The sum of 5 different positive 2-digit integers is 130. What is the highest possible value of the largest of these integers?
A.88
B.84
C.78
D.74
Answer: B.84
Explanation: sum of 5 different 2 digit integers=130
to find out the largest number, we need to make other 4 numbers to the smallest as possible.
smallest 2 digit number is 10
=>10+11+12+13+n=130
=>n=130-46=84
Answer is B
Question: In a local school district, the high school and middle school each received r dollars toward funding for the student arts program. The high school enrolled 150 students and the middle school enrolled 75 students. Later, the middle school transferred s dollars to the high school so that they would have received the same funding per student. Which of the following is equivalent to s?
A.r/8
B.r/5
C.r/2
D.r/3
Answer: D.r/3
Explanation: Total per head = 2r/225
After s transfer both schools have total for head.
So at High School it will be:
r+s = (150)* (2r/225) = 12r/9=4r/3
i.e. s = 4r/3 - r/1 =4r-3r/3=r/3
Answer :D
Question: The speed at which a man can row a boat in still water is 15 kmph. If he rows downstream, where the speed of current is 3 kmph, what time will he take to cover 60 metres?
A.65 seconds
B.14 seconds
C.14 seconds
D.12 seconds
Answer: D.12 seconds
Explanation: Speed of the boat downstream
= 15 + 3 = 18 kmph
= 18 * 5/18 = 5 m/s
Hence time taken to cover 60 m
= 60/5 =12 seconds.
Answer: D
Question: 50, 47, 45, 42, 40, 37, ?
A.36
B.35
C.34
D.33
Answer: B.35
Explanation: This is an alternating number subtraction series. The pattern is -3, -2, -3, -2, ....
The answer is B.
Question: A 4-letter code word consists of letters X, Y, and Z. If the code includes all the three letters, how many such codes are possible?
A.36
B.72
C.48
D.24
Answer: A.36
Explanation: Note that the correct answer to this question is 36, not 72.
X-XYZ can be arranged in 4!/2!=12 ways;
Y-XYZ can be arranged in 4!/2!=12 ways;
Z-XYZ can be arranged in 4!/2!=12 ways;
Total: 12+12+12=36.
Answer: A.
Question: If y exceeds x by 22%, then x is less than y by?
A.18 2/8%
B.18 8/3%
C.18 2/61%
D.76 2/3%
Answer: C.18 2/61%
Explanation: X=100	y=122
122------22
100-------? => 18 2/61%
Answer:C
Question: Two persons starting from the same place walk at a rate of 5kmph and 5.5kmph respectively. What time will they take to be 12.5km apart, if they walk in the same direction?
A.17 hrs
B.22 hrs
C.25 hrs
D.12 hrs
Answer: C.25 hrs
Explanation: The relative speed of the boys = 5.5kmph â€“ 5kmph
= 0.5 kmph
Distance between them is 12.5 km
Time= 12.5km / 0.5 kmph = 25 hrs
Answer : C.
Question: If n is a positive integer, then n(n-1)(n-2) is +ve even
A.odd whenever n is odd
B.divisible by 3 only when n is odd
C.divisible by 4 whenever n is even
D.even only when n is odd
Answer: C.divisible by 4 whenever n is even
Explanation: n*(n-1)*(n-2)= +ve even integer divisible by 4 ( e.g 6,7&8)
C
Question: In a friendship gang Andrew has 8 gang, in how many ways can he invite one or more of the gang to his house?
A.245
B.255
C.260
D.267
Answer: B.255
Explanation: Andrew can select one or more than one of his 8 gang.
=> Required number of ways = 28 – 1= 255.
B
Question: What sum of money put at C.I amounts in 2 years to Rs.8820 and in 3 years to Rs.9261?
A.Rs.8000
B.Rs.8400
C.Rs.7500
D.Rs.7800
Answer: A.Rs.8000
Explanation: 8820 ---- 441
100 ---- ? => 5%
x *105/100 * 105/100 = 8820
x*1.1025=8820
x=8820/1.1025 => 8000
ANSWER:A
Question: Find the sum of prime numbers lying between 60 and 72?
A.198
B.201
C.199
D.272
Answer: C.199
Explanation: Solution
Required sum	= 61 + 67 + 71)
= 199.
Answer C
Question: Workers decided to raise Rs.3lacs by equal contribution from each. Had they contributed Rs.50 eachextra, the contribution would have been Rs.3.25lacs. How many workers were they?
A.400
B.600
C.500
D.700
Answer: C.500
Explanation: N * 50 = (325000 - 300000) = 25000
N = 25000 / 50
= 500
C
Question: What is the greatest power that 7 can be raised to so that the resulting number is a factor of 21!?
A.2
B.3
C.4
D.5
Answer: B.3
Explanation: the number of 7s in 21!= 21/7=3..
ans B
Question: In one hour, a boat goes 11 km/hr along the stream and 5 km/hr against the stream. The speed of the boat in still water (in km/hr) is:
A.2kmph
B.3kmph
C.8kmph
D.9kmph
Answer: C.8kmph
Explanation: Speed in still water = (11+5)/2
= 8 kmph
Ans- C
Question: A, B, C hired a car for Rs. 520 and used it for 7,8 and 11 hours respectively. Hire charges paid by B were :
A.160
B.180
C.220
D.225
Answer: A.160
Explanation: Sol.
A : B : C = 7 : 8 : 11.
Hire charges paid by B = Rs. [520 * 8/26] = Rs.160
Answer A