RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: A football coach must choose 4 freshers from a team of 11 players. How many different ways can the coach choose the freshers?
A.330
B.650
C.729
D.800
Answer: A.330
Explanation: Choose 4 starters from a team of 11 players. Order is not important.
\inline {\color{Black} 11C_{4}}= 330
A
Question: There are seven thieves. They stole diamonds from a diamond merchant and ran away. While running, night sets in and they decide to rest in the jungle.
When everybody was sleeping, two of them woke up and decided to divide the diamonds equally among themselves. But when they divided the diamonds equally, one diamond is left.
So they woke up the 3rd thief and tried to divide the diamonds equally again but still one diamond was left. Then they woke up the 4th thief to divide the diamonds equally again, and again one diamond was left. This happened with the 5th and 6th thief – one diamond was still left.
Finally, they woke up the 7th thief and this time the diamonds were divided equally.
How many diamonds did they steal in total?
A.2397
B.2401
C.2411
D.2423
Answer: B.2401
Explanation: We need a number that is a multiple of 7 that will give a remainder of 1 when divided by 2, 3, 4, 5, and 6. The least common multiple of these numbers is 60. So, we need a multiple of 7 that is 1 greater than a multiple of 60.
Answer B
Question: Three is the largest number that can be divided evenly into 27 and the positive integer x, while 10 is the largest number that can be divided evenly into both 100 and x. Which of the following is the largest possible number that could be divided into x and 2100
A.30
B.70
C.210
D.300
Answer: C.210
Explanation: Since 3 is the GCF of 27 (3.3.3) and x => x has only one "3 in its prime box.
Since 10 (2.5) is the GCF of 100 (2.2.5.5) and x => x has only one 2 and one 5 in its primebox.
So x = 2.3.5.n (n=something that is not 2, 3, 5)
2100 = 2.3.5.7 =210
The GCF of x and 2100 is the product of the common factors of x and 2100 => the max possible is 2100.
ANSWER:C
Question: Increasing the original price of an article by 15% and then increasing the new price by 15% again is equivalent to increasing the original price by what %?
A.34
B.40
C.68
D.88
Answer: A.34
Explanation: Let the price of a commodity is increased by a% and then b% then the final increment will be
1 + a/100 + b/100 + ab/10000
Now the same logic can be applied with decrements also with just changing the signs.
Let for example price of commodity is increased by a% and then decreased by b% then the resulting increase/decrease will be
1 + a/100 - b/100 -ab/10000
For the above question the approach will be
1 + 0.15 + 0.15 + 0.0225 = 1.3225 ==> 32.25%
Closest answer is A
Question: Which of the following is a prime number ?
A.33
B.81
C.97
D.93
Answer: C.97
Explanation: Clearly, 97 is a prime number
Question: The average of first seven prime numbers which are between 30 and 70 is
A.35.4
B.42
C.44.4
D.57
Answer: C.44.4
Explanation: Explanation :
first seven prime numbers which are between 30 and 70 = 31, 37, 41, 43, 47, 53, 59
average = (31 + 37 +41 + 43 + 47 + 53 + 59)/7
= 44.4
Answer : C
Question: Mark has to visit towns B and C in any order. The roads connecting these towns with his house are shown on the diagram. How many different routes can he take starting from A and returning to A, going through both B and C and not traveling any road twice on the same trip?
A.5
B.8
C.9
D.10
Answer: B.8
Explanation: Mark can travel clockwise or anticlockwise on the diagram.
Clockwise, he has no choice of route from A to B, a choice of one out of two routes from B to C, and a choice of one out of two routes from C back to A. This gives four possible routes.
Similarly, anticlockwise she has four different routes.
Total routes = 8
B
Question: When Professor Wang looked at the rosters for this term's classes, she saw that the roster for her economics class (E) had 26 names, the roster for her marketing class (M) had 26, and the roster for her statistics class (S) had 18. When she compared the rosters, she saw that E and M had 9 names in common, E and S had 7, and M and S had 10. She also saw that 4 names were on all 3 rosters. If the rosters for Professor Wang's 3 classes are combined with no student's name listed more than once, how many names will be on the combined roster?
A.30
B.34
C.48
D.46
Answer: C.48
Explanation: Total # of students 26+26+18-(9+7+10)+4=48.
Answer: C.
Question: A dealer purchased an article at 3/4 of its list price and sold 50% more than the list price. Find his gain percent?
A.106%
B.200%
C.100%
D.170%
Answer: C.100%
Explanation: MP = 100
CP = 75
SP = 150
------
75 ---- 75
100 ---- ? => 100%
Answer: C
Question: If n and y are positive integers and 450y = n^3, which of the following must be an interger
I. y/ (3 * 2^2 * 5)
II. y/ (3^2 * 2 * 5)
III. y/ 3 * 2 * 5^2
A.None.
B.I only.
C.II only.
D.III only.
Answer: B.I only.
Explanation: 450 y = n^3 -> y = n3/450 -> n3 is divisible by 450 & n is +ve integer. look for values of n^3 such that n is integer and n is divisible by 450. Clearly we have to look in the order of 1000's to find a value such that n3 is divisible by 450 and n is integer.
n3=1000 n =10 not divisible by 450
n3=8000 n =20 not divisible by 450
n3=27000 n =30 divisible by 450 y = 2700/45 = 60
Look for I, II , III which have denominators 60,90,150.
only I does and hence B
Question: The ratio of three numbers is 3:4:5 and the sum of their squares is 1250. The sum of the numbers is:
A.30
B.50
C.60
D.70
Answer: C.60
Explanation: Let the numbers be 3x, 4x and 5x
Then, 9x2+16x2+25x2=1250
50x2=1250
X=5
Sum of numbers= 3x+4x+5x=12x=60
ANSWER C 60
Question: A company assigns product codes consisting of all the letters in the alphabet.How many product codes are possible if the company uses at most 2 letters in its codes, and all letters can be repeated in any one code?
A.A.702
B.B.16226
C.C.17576
D.D.18278
Answer: A.A.702
Explanation: The no of ways in which the company can make codes of 1 letter : 26
# for 2 letters : 26*26 = 676
The total : By adding all of them , 676+26= 702
A.
Question: A bike covers a certain distance at the speed of 81km/h in 7 hrs. If the bike was to cover the same distance in approximately 9 hrs, at what approximate speed should the bike travel?
A.80 km/h
B.67 km/h
C.90.14 km/h
D.63 km/h
Answer: D.63 km/h
Explanation: Ans.(D)
Sol. Total distance = 81 × 7 = 567 km
Now speed = 567/9 = 63 km/h
Question: There are k-2 members in a certain band, including Jim and Ellen. Two members are to be selected to attend the Grammy awards ceremony. If there are 21 possible combinations in which Jim and Ellen are not selected, what is the value of k?
A.8
B.9
C.10
D.11
Answer: D.11
Explanation: There are k-2 members in the band, and k-4 members without Jim and Ellen.
(k-4)C2 = 21
(k-4)(k-5)/2 = 21
(k-4)(k-5) = 42 = 7*6
k = 11
The answer is D.
Question: A number when divided by 6 leaves a remainder 3. When the square of the same number is divided by 6, the remainder is:
A.0
B.1
C.2
D.3
Answer: D.3
Explanation: Let x=6q+3. Then, x2= (6q+3)2= 36q2+36q+9= 6(6q2+6q+1)+3.
So, when 2n is divided by 4, remainder =3.
Answer: D
Question: When n is divided by 20, the remainder is 6. What is the remainder when n + 16 is divided by 5?
A.1
B.3
C.4
D.5
Answer: A.1
Explanation: Assume n = 14
Remainder (n/20) = 6
n+16 = 36
Remainder (36/5) = 1
Option A
Question: Carol and Jordan draw rectangles of equal area. If Carol's rectangle measures 5 inches by 24 inches and Jordan's rectangle is 4 inches long, how wide is Jordan's rectangle, in inches?
A.25
B.23
C.32
D.30
Answer: D.30
Explanation: Area of Carol's rectangle = 24*5 = 120
Let width of Jordan's rectangle= w
Since , the areas are equal
4w = 120
=>w = 30
Answer D
Question: A man can row 3.6 km/hr in still water. It takes him twice as long to row upstream as to row downstream. What is the rate of the current ?
A.1.9
B.1.7
C.1.2
D.1.5
Answer: C.1.2
Explanation: Speed of boat in still water (b) = 3.6 km/hr. Speed of boat with stream (Down Stream), D = b + u Speed of boat against stream (Up stream), U = b – u It is given upstream time is twice to that of down stream. ⇒ Downstream speed is twice to that of upstream. So b + u = 2(b – u) ⇒ u =b/3 = 1.2 km/hr.
Answer: C
Question: A, B and C have Rs.500 between them, A and C together have Rs.200 and B and C Rs.350. How much does C have?
A.50
B.76
C.27
D.26
Answer: A.50
Explanation: A+B+C = 500
A+C = 200
B+C = 350
--------------
A+B+2C = 550
A+B+C = 500
----------------
C = 50
Answer:A
Question: The average score of 35 students in a class is 37. If every student is given 3 grace marks, the new average of the class is:
A.33
B.21
C.38
D.40
Answer: D.40
Explanation: Explanation:
Average score = 37
Grace mark 3 is given to 35 student then its average will be 3.
Hence new average = 37 + 3 = 40
Answer: D
Question: The sector of a circle has radius of 21 cm and central angle 120o. Find its perimeter?
A.91.5 cm
B.11.5 cm
C.91.8 cm
D.86 cm
Answer: D.86 cm
Explanation: Perimeter of the sector = length of the arc + 2(radius)
= (120/360 * 2 * 22/7 * 21) + 2(21)
=44 + 42
= 86 cm
Answer:D
Question: Earl can stuff advertising circulars into envelopes at the rate of 36 envelopes per minutes and Ellen requires a minutes and half to stuff the same number of envelops.Working together,how long will it take Earl and Ellen to stuff 60 envelopes
A.1 minute
B.5 minutes
C.7 minutes
D.3 minutes
Answer: A.1 minute
Explanation: earl takes 1 min. for 36 envelopes.
ellen takes 3/2 mins for the same. so ellen can stuff ((36)/(3/2)) in 1 min. i.e., 24 envlpes a min.
so both of them when work together can stuff 36+24=60 envelopes in 1 min.
for 60 envelopes they will take 60/60 mins. i.e., 1 mins.
ANSWER:A
Question: Find out the C.I on Rs.5000 at 4% p.a. compound half-yearly for 1 1/2 years.
A.306.05
B.306.00
C.306.04
D.306.05
Answer: A.306.05
Explanation: A = 5000(51/50)3
= 5306.04
5000
-----------
306.04
Answer: A
Question: The mean of 50 observations is 200. But later he found that there is decrements of 15 from each observations. what is the the updated mean is ?
A.170
B.185
C.190
D.198
Answer: B.185
Explanation: 185
Answer is B
Question: A container contains 20 liters of milk, From this container 2 liters of milk was taken out and replaced by water. This process was repeated further 2 times. How much milk is now contained by the container?
A.14.58 liters
B.20.16 liters
C.22.45 liters
D.26.95 liters
Answer: A.14.58 liters
Explanation: Amount of milk left after 3 operations = 20 (1 - 2/20)^3 = 20 * 9/10 * 9/10 * 9/10 = 14.58 liters
Answer is A
Question: Tough and Tricky questions: Arithmetic.
(8^2 + 8^2)/4^2 =
A.4
B.29
C.8
D.58
Answer: C.8
Explanation: Ans is 8
my approach was:
(8^2 + 8^2)/4^2 =8(8+8)/4*4
=8*16/4*4=2*4=8
C
Question: Two trains 140 m and 160 m long run at the speed of 60 km/hr and 40 km/hr respectively in opposite directions on parallel tracks. The time which they take to cross each other is?
A.10.6
B.10.9
C.10.4
D.10.8
Answer: D.10.8
Explanation: Relative speed = 60 + 40 = 100 km/hr.
= 100 * 5/18 = 250/9 m/sec.
Distance covered in crossing each other = 140 + 160 = 300 m.
Required time = 300 * 9/250 = 54/5 = 10.8 sec.
Answer: D
Question: If -y^2= 2xy, then (x+y)^2 =
A.x^2
B.3x^2
C.4xy
D.2y^2
Answer: A.x^2
Explanation: Its B
-y^2 = 2xy
0 = 2xy + y^2
Add x^2 on both sides we get
x^2 +0 = x^2 +y^2 +2xy
x^2 = (x+y)^2
Correct Option : A
Question: Lion, rat stay in jungle happily. Lion lies on: Mon, Tue, Wed. Rat lies on: Wed, Thurs , Sat. If lion says: I didn't lie yesterday. Rat says: I didn’t lie yesterday. So what day is today?
A.Tuesday
B.wednesday
C.Thursday
D.Friday
Answer: A.Tuesday
Explanation: Tuesday -- lion ll tell lie on tuesday
lion is saying lie that he didn't lie sday [ again a lie... bcozzz lion ll say lie on monday also]
Tuesday -- Rat ll not say lie on tuesday
ANSWER:A
Question: 64 Ã— 64 Ã— 64 Ã— 64 x 64 =8 ^?
A.4
B.7
C.8
D.10
Answer: D.10
Explanation: 64 Ã— 64 Ã— 64 Ã— 64 x 64 = 8^?
or, 8(2) Ã— 8(2) Ã— 8(2) Ã— 8(2) x 8(2) = 8?
or 7(10) = 8? or, ? = 10
Answer D
Question: 337.62+5.628+33.4=?
A.376.648
B.112.6
C.258.69
D.5874.3
Answer: A.376.648
Explanation: 337.62
5.628
33.4
----------
376.648
Answer is A
Question: What is the least common multiple of 12,27 and 40
A.8521
B.1080
C.368
D.8979
Answer: B.1080
Explanation: factors of 12 =2*2*3
factors of 27= 3*3*3
factors of 40 =2*2*2*5
thus the l.c.m is 2^3*3^3*5=1080
the answer is B
Question: A right triangle STU has an area=30. If the longest side of the triangle is SU and value of ST=5. What are the lengths of sides TU and SU?
A.12, 13
B.5, 13
C.24, 26
D.12, 24
Answer: A.12, 13
Explanation: Area=30 and ST=5. By applying Area=STxTU, we get that TU=12, which is the first part of our answer.
By Pythagorean Theorem, we can now find the value of SU since we have value of ST and we found value of TU. So the correct answer is A.
Question: The total car population in a Mumbai is 2,94,00 out of which 1,50,00 are made by Honda. Out of every 100 Honda cars, 98 are red in color, but only 53% of the total car population is red. Find the % of non-Honda cars that are red
A.2.54%
B.4.56%
C.6.125%
D.7.134%
Answer: C.6.125%
Explanation: Total Car.29.10 i.e., Honda +non Honda = 29400 Given: Whim. tractor .150W
Now,5346 of 2..00 = Honda +Red Non-Honda 29400 .:4 =15582 Thus...El Mall... 1.0 Now Honda 15582 flow, Non-. Honda =15582 - 15.582-14700=8B2 96 non-Honda =1=1.100 = 6.125%
C
Question: A train 100 meters long completely crosses a 300 meters long bridge in 45 seconds. What is the speed of the train is?
A.32
B.27
C.88
D.26
Answer: A.32
Explanation: S = (100 + 300)/45 = 400/45 * 18/5
= 32
Answer:A
Question: the difference between a positive fraction and its reciprocal is 9/20 find the sum of that fraction and its reciprocal.
A.41/20
B.17/20
C.11/20
D.9/20
Answer: A.41/20
Explanation: Explanation :
Let the fraction = x
Then x − (1/x) = 9/20
⇒ (x2 − 1)/x = 9/20
⇒ x2 − 1 = 9x/20
⇒ 20x2 − 20 = 9x
⇒ 20x2 − 9x − 20 = 0
x=−b±b2−4ac√2ax=−b±b2−4ac2a =9±(−9)2−4×20×(−20)√2×20=9±(−9)2−4×20×(−20)2×20 =9±81+1600√40=9±4140=5040Or−3240=9±81+160040=9±4140=5040Or−3240
Given that the fraction is positive. Hence
x = 50/40 = 5/4
1/x = 4/5
x + (1/x) = (5/4) + (4/5) = (5 × 5 + 4 × 4)/20 = 41/20. Answer : Option A
Question: Find the least number must be subtracted from 5264 so that remaining number is divisible by 17.
A.11
B.14
C.18
D.20
Answer: A.11
Explanation: When dividing 5264 by 17, we get the remainder 11, so 11 should be subtracted. The answer is A.
Question: The probability of a lottery ticket being a prized ticket is 0.2. When 4 tickets are purchased, the probability of winning a prize on atleast one ticket is
A.0.5928
B.0.5904
C.0.5297
D.0.5297
Answer: B.0.5904
Explanation: P(winning prize atleast on one ticket)
= 1 - P("Losing on all tickets")
= 1 - (0.8)4 = (1 + (0.8)2)(1 - (0.8)2)
= (1.64)(0.36)
= 0.5904
Answer:B
Question: The sum of the ages of a father and son is 45 years. Five years ago, the product of their ages was four times the fathers age at that time. The present age of father and son
A.6
B.7
C.9
D.2
Answer: C.9
Explanation: Let sons age = x years. Then fathers age = (45 - x)years.
(x—5)(45—x—5) = 4(45- x - 5) hence (x—5) = 4 so x = 9
Their ages are 36 years and 9 years.
Answer: C
Question: There are 20,6 and 9 rupees notes. you have to form 99 rupees with minimum number of notes.At what minimum number of notes you can achieve this?
A.9
B.8
C.7
D.6
Answer: A.9
Explanation: 20*3 = 60
6*2 = 12
9*2 = 18
9*1 = 9
9 notes
ANSWER:A
Question: It is known that no more than 6 children will be attending a party. What is the smallest number of cookies that must be brought to the party so that each child receives the same number of cookies?
A.35
B.105
C.60
D.210
Answer: C.60
Explanation: The question states that there are no more than 6 children in the party. Thus, the possibility is that there could be 1, 2, 3, 4, 5 or 6 children.
If you assume answer as 35 and there are 3 children, you may not distribute be able to distribute cookies equally.
similarly if there were 105 cookies, and 2 children, cookies cannot be distributed equally.
or if there were 210 cookies, and 4 children, cookies cannot be distributed equally.
Thus, the question asks for a number of cookies which can be distributed to any number of children (from 1 to 6).
And therefore the smallest number of cookies would be lcm of (1, 2, 3, 4, 5, 6), i.e., 60.
Answer (C)
Question: If the tens digit x and the units digit y of a positive integer n are reversed, the resulting integer is 18 more than n. What is y in terms of x ?
A.x+2
B.x-2
C.x+5
D.x+6
Answer: A.x+2
Explanation: Original Digits=xy i.e. Number=10x+y
After reversing the digits:
Digits=yx i.e. Number=10y+x
10y+x is 18 more than 10x+y
10x+y+18=10y+x
10x-x+18=10y-y
9x+18=9y
x+2=y
OR
y=x+2
Answer : A
Question: As a treat for her two crying children, a mother runs to the freezer in which she has two cherry ice pops, three orange ice pops, and four lemon-lime ice pops. If she chooses two at random to bring outside to the children, but realizes as she runs out the door that she cannot bring them different flavors without one invariably being jealous of the other and getting even more upset, what is the probability that she has to return to the freezer to make sure that they each receive the same flavor?
A.1/9
B.1/6
C.5/18
D.13/18
Answer: D.13/18
Explanation: Probability of not getting the same flavor ->
Favorable -> Cherry - orange [ 2C1 * 3C1 [or simply 2*3 ] or Cherry - lemon [ 2*4] or orange - lemon [3*4]
Prob = (2*3 + 2*4 + 3*4 ) / 9C2 = 26/36 = 13/18
Answer -> D
Question: In a class, 30% of the students offered English, 20% offered Hindi and 10% offered both. If a student is selected at random, what is the probability that he has offered English and Hindi?
A.2/10
B.1/10
C.3/10
D.2/5
Answer: D.2/5
Explanation: P(E)=30/100,
P(H)=20/100
P(E and H)=10/100
P(E or H)=3/10+2/10-1/10
=2/5
ANSWER D 2/5
Question: The length of a rectangular field is 7/5 its width. If the perimeter of the field is 336 meters, what is the width of the field?
A.50
B.60
C.70
D.80
Answer: C.70
Explanation: Let L be the length and W be the width. L = (7/5)W
Perimeter: 2L + 2W = 336, 2(7/5)W + 2W = 336
Solve the above equation to find: W = 70 m and L = 98 m.
correct answer C)70
Question: Of the teams competing in the world archery championships, sixty percent are from Europe. Half as many are from the United States and one twentieth are from Africa. What fraction of teams are from neither Europe, the US or Africa.
A.1/20
B.15/20
C.13/15
D.17/20
Answer: A.1/20
Explanation: Assume 100 total people.
60% of 100 = 60 --->Europeans
1/2 of 60 ---> 30 Americans
1/20 of 100 ---> 5 Africans
Now you would add them all up, and minus it by the total (100). 100 - 95= 5. So, 65 people out of 100 are not EU, US or Africans. 5/100 is also equal to 1/20.
So therefore, the answer is A.
Question: When positive integer N is divided by positive integer J, the remainder is 42. If N/J = 204.07, what is value of J?
A.200
B.400
C.800
D.600
Answer: D.600
Explanation: When a number is divided by another number, we can represent it as : Dividend = Quotient * Divisor + Remainder
So, Dividend/Divisor = Quotient + Remainder/Divisor
Given that N/J = 204.07
Here 204 is the quotient.
Given that Remainder = 42
So, 204.07= 204 + 42/J
So, J = 600
Answer: D
Question: I bought two books; for Rs.470. I sold one at a loss of 15% and other at a gain of 19% and then I found each book was sold at the same price. Find the cost of the book sold at a loss?
A.274.17
B.280.17
C.299.17
D.266.17
Answer: A.274.17
Explanation: x*(85/100) = (470 - x)119/100
x = 274.17
Answer: A
Question: A certain sum is invested at simple interest at 15% p.a. for two years instead of investing at 12% p.a. for the same time period. Therefore the interest received is more by Rs. 420. Find the sum?
A.s. 5000
B.s. 7000
C.s. 14000
D.s. 17000
Answer: B.s. 7000
Explanation: Let the sum be Rs. x.
(x * 15 * 2)/100 - (x * 12 * 2)/100 = 420
=> 30x/100 - 24x/100 =420
=> 6x/100 = 420
=> x = 7000.
ANSWER:B
Question: The average of 13 numbers is 58. Average of the first 7 of them is 57 and that of the last 7 is 61. Find the 8th number?
A.72
B.83
C.45
D.53
Answer: A.72
Explanation: Sum of all the 13 numbers = 13 * 58 = 754
Sum of the first 7 of them = 7 * 57 = 399
Sum of the last 7 of them = 7 * 61 = 427
So, the 8th number = 427 + 399 - 754 = 72.
Answer:A
Question: Two trains of length 100 m and 200 m are 100 m apart. They start moving towards each other on parallel tracks, at speeds 18 kmph and 72 kmph. In how much time will the trains cross each other?
A.8
B.16
C.11
D.12
Answer: B.16
Explanation: Relative speed = (18 + 72)* 5/18 = 25 mps.
The time required = d/s = (100 + 100 + 200)/25
= 400/25 =16 sec.
Answer:B
Question: The population of a bacteria colony doubles every day. If it was started 9 days ago with 2 bacteria and each bacteria lives for 12 days, how large is the colony today?
A.512
B.768
C.1024
D.2048
Answer: C.1024
Explanation: It started 9 days ago. So bacterias keep growing for 9 days+ today= 10 days
2^10= 1024
C is the answer
Question: Sum of 3 consecutive even no.'s is 28 more than the 1st no. of the series. Find the middle no.?
A.8
B.13
C.14
D.16
Answer: B.13
Explanation: Let the numbers be x, x+2 and x+4 then
x + x+2 + x+4 = x+28
3x + 6 = x + 28
2x = 22
\inline \therefore x = 11
\inline \therefore Middle number = x + 2 = 11+2 = 13
B
Question: 5^b + 5^b + 5^b + 5^b + 5^b =
A.5^(b + 1)
B.7^(b + 1)
C.7^(7b)
D.8^b
Answer: A.5^(b + 1)
Explanation: Easy one.
5*5^b = 5^(b+1)
Ans. A
Question: The present population of a town is 1000. Population increase rate is 20% p.a. Find the population of town after 2 years?
A.1440
B.1220
C.1400
D.1500
Answer: A.1440
Explanation: P = 1000
R = 20%
Required population of town = P*(1 + R/100)^T
= 1000*(1 + 20/100)^2
= 1000*(6/5)^2
= 1440(approximately)
Answer is A
Question: What is the average of first 20 multiples of 7 ?
A.A)70
B.B)77
C.C)79
D.D)84
Answer: D.D)84
Explanation: Required average = 7(1+2+....+20) / 20
(8/20)X ( (20x21) / 2 ) (because sum of first 21 natural numbers)
= 84
D
Question: How many numbers between 200 and 600 are divisible by 4, 5 and 6?
A.5
B.6
C.8
D.10
Answer: B.6
Explanation: Sol.
Every such numbers must be divisible by L.C.M. of 4, 5, 6, i.e. 60.
Such numbers are 240, 300, 360, 420, 480, 540.
Clearly, there are 6 such numbers.
Answer B
Question: A pair of prime numbers that can be expressed in the form {p, (p + 6)} is deﬁned as a pair of “sexy primes.” A “sexy triplet” is a group of three primes that can be expressed in the form Q{p, (p + 6), (p + 12)}. All of the following prime numbers are the middle term of a sexy triplet EXCEPT
A. 11
B. 13
C. 17
D. 19
Answer: D. 19
Explanation: definetly a sitter.plug in the values for middle term and calculate.We can see clearly that Q for 19 , 19+6 gives 25 which is not a prime
therefore correct answer D
Question: A, B and C started a business with capitals of Rs. 8000, Rs. 10000 and Rs. 12000 respectively. At the end of the year, the profit share of B is Rs. 4000. The difference between the profit shares of A and C is?
A.621
B.276
C.236
D.1600
Answer: D.1600
Explanation: Explanation:
Ratio of investments of A, B and C is 8000 : 10000 : 12000 = 4 : 5 : 6
And also given that, profit share of B is Rs. 4000
=> 5 parts out of 15 parts is Rs. 4000
Now, required difference is 6 - 4 = 2 parts
Required difference = 2/5 (4000) = Rs. 1600
Answer: D
Question: In a nationwide poll, N people were interviewed. If 1/6 of them answered yes to question 1, and of those, 1/4 answered yes to question 2, which of the following expressions represents the number of people interviewed who did NOT answer yes to both questions?
A.N/10
B.9N/10
C.2N/3
D.23N/24
Answer: D.23N/24
Explanation: The number of people who answered yes to both questions is (1/4)(1/6)N = N/24
The number of people who did not answer yes to both is 1 - N/24 = 23N/24
The answer is D.
Question: P, Q, R enter into a partnership. P initially invests 25 lakh & adds another 10 lakhs after one year. Q initially invests 35 lakh & withdrawal 10 lakh after 2 years and R invests Rs 30 Lakhs . In what ratio should the profit be divided at the end of 3 years?
A.18:19:19
B.18:18:19
C.19:19:18
D.18:19:19
Answer: C.19:19:18
Explanation: Solution: P:Q:R = (25*1+35*2) : (35*2 : 25*1) : (30*3)
= 95 : 95 : 90.
= 19 : 19: 18.
Answer: Option C