RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: The average age of husband, wife and their child 3 years ago was 27 years and that of wife and the child 5 years ago was 20 years. The present age of the husband is?
A.65 years
B.40 years
C.54 years
D.46 years
Answer: B.40 years
Explanation: Sum of the present ages of husband, wife and child
= (27 * 3 + 3 * 3) = 90 years.
Sum of the present age of wife and child
= (20 * 2 + 5 * 2) = 50 years.
Husband's present age
(90 - 50) = 40 years.
Answer:B
Question: Two cars started at the same time, from the same point, driving along the same road. The rate of the first car is 50 mph and the rate of the second car is 60 mph. How long will it take for the distance between the two cars to be 30 miles?
A.1 hrs
B.2 hrs
C.3 hrs
D.4 hrs
Answer: C.3 hrs
Explanation: car 1 50 50 50 total=150
car 2 60 60 60 total=180 differece=30miles after 3 hrs.
ANSWER:C
Question: A starts business with Rs.3500 and after 9 months, B joins with A as his partner. After a year, the profit is divided in the ratio 2 : 3. What is Bâ€™s contribution in the Capital ?
A.24887
B.20778
C.23788
D.21000
Answer: D.21000
Explanation: Explanation:
A invested Rs.3500 for 12 months.
Let B joined with investment x. And he invested for 12 - 9 = 3 months.
So there profit ratio = (3500 Ã— 12) : (3x) = 2 : 3
â‡’ x = 21000
Answer: D
Question: Rajeev's age after 15 years will be 5 times his age 5 years back. What is the present age of Rajeev?
A.5 years
B.10 years
C.20 years
D.25 years
Answer: B.10 years
Explanation: Solution
Let Rajeev's present age be x years. Then
Rajeev's age 15 years	= (x+15) years.
Rajeev's age 5 years back	= (x-5) years.
Therefore	‹=› x+15=5(x-5)
‹=› x+15= 5x-25
‹=› 4x=40
‹=› x=10.
Answer B
Question: A certain barrel, which is a right circular cylinder, is filled to capacity with 50 gallons of oil. The first barrel is poured into a second barrel, also a right circular cylinder, which is empty. The second barrel is twice as tall as the first barrel and has twice the diameter of the first barrel. If all of the oil in the first barrel is poured into the second barrel, how much empty capacity, in gallons, is left in the second barrel?
A.There is no empty capacity
B.100 gallons
C.350 gallons
D.700 gallons
Answer: C.350 gallons
Explanation: Radius of first cylinder=r, diameter=2r, height=h
Radius of second cylinder=2r, diameter=2d and height=2h
Volume of first cylinder=pie (r^2)*h=50
Volume of second cylinder=pie(2r^2)2h
Put the value of pie (r^2)*h=50 in the second cylinder,volume= pie (r^2)*4*2=50*8=400 gallons
Empty capacity=350 gallons
Answer C
Question: Suresh started a business with Rs.20,000. Kiran joined him after 4 months with Rs.30,000. After 2 more months, Suresh withdrew Rs.5,000 of his capital and 2 more months later, Kiran brought in Rs.20,000 more. What should be the ratio in which they should share their profits at the end of the year?
A.21:32
B.32:21
C.12:17
D.17:12
Answer: A.21:32
Explanation: Here capital is not the same.
Suresh invested 20000 for initial 6 months and 15000 for the next 6 months. Hence his term of ratio
=(20000×6+15000×6)
Kiran invested Rs.30000 for 4 months and Rs.50000 for next 4 months. Hence his term of ratio
=(30000×4+50000×4)
Suresh : Kiran
=(20000×6+15000×6):(30000×4+50000×4)
=(20×6+15×6):(30×4+50×4)=(20×3+15×3):(30×2:50×2)
=105:160
=21:32 Answer: Option A
Question: If m and n are both negative and mn < n^2, which of the following must be true?
A.m < n < m^2 < n^2
B.m < n < n^2 < m^2
C.n < m < m^2 < n^2
D.m^2 < n^2 < n < m
Answer: C.n < m < m^2 < n^2
Explanation: Because mn < n^2 and both are negative, I thought m < n. So I crossed off answers c), d), and e).
And because m < n , m^2 < n^2
ans C
Question: If p/q =4/5, then the value of 6/7 + {(2q - p) / (2q + p)} is ?
A.3 / 7
B.34
C.10/7
D.2
Answer: C.10/7
Explanation: Answer
Given Exp. = 6 / 7 + {(2q - p) / (2q + p)}
Dividing numerator as well as denominator by q,
Exp = 6/7 + {2-p/q) / (2 + p/q)}
= 6/7 + {(2 - 4/5) / (2 + 4/5)}
= 6/7 + 6/14
= 6/7 + 3/7
=10/7
Correct Option: C
Question: In 10 years,A will be thrice as old as B was 10 years ago.If A is now 9 years older than B,the present age of B is :
A.19 Years
B.24.5 Years
C.39 Years
D.49 Years
Answer: B.24.5 Years
Explanation: Solution
Let B's present age = x years.Then,A's present age =(x +9) years.
âˆ´ (x + 9)+ 10 = 3 (x - 10) â‡” x + 19 = 3x- 30 â‡” 2x = 49 x = 24.5.Answer B
Question: Two pipes can fill a tank in 18 minutes and 15 minutes. An outlet pipe can empty the tank in 45 minutes. If all the pipes are opened when the tank is empty, then how many minutes will it take to fill the tank?
A.30 minutes
B.17 minutes
C.15 minutes
D.10 minutes
Answer: D.10 minutes
Explanation: Part of the filled by all the three pipes in one minute
= 1/18 + 1/15 - 1/45 = (5 + 6 - 2)/90 = 9/90 = 1/10
So, the tank becomes full in 10 minutes.
Answer: D
Question: How long does a bus 100 m long traveling at 50 kmph takes to cross a bridge of 150 m in length?
A.18
B.16
C.15
D.11
Answer: A.18
Explanation: D = 100 + 150 = 250 m
S = 50 * 5/18 = 125/9
T = 250 * 9/125 = 18 sec
Answer:A
Question: Which of the following integers is a divisor of(15!+12)?
A.15
B.14
C.12
D.7
Answer: C.12
Explanation: When we say 15!, it just means 1*2*3*4*5*...*13*14*15
So you need to find the integer which is a divisor of
(1*2*3*4*5*...*13*14*15 + 12) = 12 (1*2*3*4*5*...11*13*14*15 + 1) We obtain this by taking 12 common.
Hence 12 is definitely a divisor of (15! + 12).
C
Question: Pipe A can fill a tank in 16 minutes and pipe B cam empty it in 24 minutes. If both the pipes are opened together after how many minutes should pipe B be closed, so that the tank is filled in 30 minutes?
A.21
B.22
C.25
D.26
Answer: A.21
Explanation: 30/16 - x/24 = 1 => x/24 = 30/16 - 1 = 14/16
=> x = 14/16 * 24 = 21.
ANSWER A
Question: Based on this year's costs, an orcharde grower budgets P dollars for planing N new trees next year. If the average cost of planting each tree were to increase 25% from this year's cost, then the greatest number of trees that the orchard grower could plant next year using P dollars would be
A.20% less than N
B.25% less than N
C.equal to N
D.20% greater than N
Answer: A.20% less than N
Explanation: This year, the price of a tree is price1=P/N.
If this price increases by 25% it becomes price 2=P/N*1.25
Then with P dollars, you can grow P/price 2 tress i.e. P/(P/N*1.25) i.e. N/1.25 i.e. .80*N
Correct answer is (A).
Question: The number of new words that can be formed by rearranging the letters of the word 'ALIVE' is
A.288
B.767
C.119
D.287
Answer: C.119
Explanation: Explanation:
Number of words which can be formed = 5! - 1 = 120 - 1 = 119.
Answer: C
Question: The floor of a rectangular room is 17 m long and 12 m wide. The room is surrounded by a veranda of width 2 m on all its sides. The area of the veranda is :
A.124 m2
B.132 m2
C.148 m2
D.152 m2
Answer: B.132 m2
Explanation: Area of the outer rectangle = 21 Ã— 16 = 336 m2
Area of the inner rectangle = 17 Ã— 12 = 204 m2
Required area = (336 â€“ 204) = 132 m2
Answer B
Question: There are two positive numbers in the ratio 5 : 8. If the larger number exceeds the smaller by 15, then find the smaller number?
A.25
B.24
C.28
D.88
Answer: A.25
Explanation: Let the two positive numbers be 5x and 8x respectively.
8x - 5x = 15 => 3x = 15 => x = 5.
Smaller number = 5x = 25.
Answer:A
Question: Insert the missing number.
7, 26, 63, 124, 215, 342, (....)
A.222
B.737
C.388
D.511
Answer: D.511
Explanation: Numbers are (23 - 1), (33 - 1), (43 - 1), (53 - 1), (63 - 1), (73 - 1) etc.
So, the next number is (83 - 1) = (512 - 1) = 511.
Answer:D
Question: A crew can row a certain course up the stream in 84 minutes; they can row the same course down stream in 7 minutes less than they can row it in still water. How long would they take to row down with the stream
A.45 or 23 minutes
B.73 or 12 minutes
C.77 minutes
D.19 minutes
Answer: C.77 minutes
Explanation: A method has been discussed here to nullify the calculations though.
All I can input here is,
speed of a crew in still water = 1/2 ( speed upstream + speed downstream)
approximating this for time,
t = 1/2(84+ (t-7))
giving t = 77
C
Question: A rectangular circuit board is designed to have a width of W inches, a length of L inches, a perimeter of P inches, and an area of Y square inches. Which of the following equations must be true?
A.2W^2 + PW + 2Y = 0
B.W^2 − PW + 2Y = 0
C.2W^2 − PW − 2Y = 0
D.W^2 + PW + Y = 0
Answer: B.W^2 − PW + 2Y = 0
Explanation: P = 2(L+W)-----------------1)
Y= LW------------------------2)
option A is not possible why ?? because all the terms are positive.
lets try option B , put value of P and A from 1 and 2 we have,
2W^2-2(L+W)W + 2(LW)
2W^2 - 2LW - 2W^2 + 2LW=0.
hence answer is B.
Question: Kyle received a bag of 82 marbles for his birthday. If he shares his marbles equally with his 5 best friends (including himself) how many more marbles will he have than his friends?
A.1 marble
B.2 marbles
C.3 marbles
D.4 marbles
Answer: D.4 marbles
Explanation: In order to divide the marbles into 6 parts, the amount must be divisible by 6.
Divisibility rule of 6: A number is divisible by 6 if it is divisible by both 2 and 3
Divisibility rule of 3: A number is divisible by 3 if the sum of the digits is divisible by 3
We need to make subtract an even this number even in order for it to be divisible by 2.
sum of digits of 82 = 10 and 6 is divisible by 3. Subtracting 4 yeilds an even number.
Hence we need to subtract 4 for the number to be divisible by 6.
Correct Option: D
Question: Two numbers are in the ratio 3:5. If 9 is subtracted from each, the new numbers are in the ratio 12:23. The smaller number is:
A.15
B.33
C.58
D.56
Answer: B.33
Explanation: Let the numbers be 3x and 5x.
Then, (3x - 9)/(5x - 9)
= 12/23
9x = 99 => x = 11
The smallest number
= 3 * 11 = 33.
AnswerB
Question: In May Mrs Lee's earnings were 60 percent of the Lee family's total income. In June Mrs Lee earned 10 percent more than in May. If the rest of the family's income was the same both months, then, in June, Mrs Lee's earnings were approximately what percent of the Lee family's total income ?
A.62%
B.68%
C.72%
D.76%
Answer: A.62%
Explanation: Let in May Lee family's total income =100
in May Mrs Lee's income =60
in May rest of the family's income = 40
In june Mrs Lees income = 60*110/100 = 66
In june Total income = 66+ 40 = 106
% of Mrs Lee's income = 66/106 =62.26
(A)
Question: One half of a two digit number exceeds its one third by 9. What is the sum of the digits of the number?
A.A)3
B.B)5
C.C)7
D.D)9
Answer: D.D)9
Explanation: x/2 – x/3 = 9 => x =54
5 + 4 = 9
ANSWER:D
Question: A, B, C and D enter into partnership. A subscribes 1/3 of the capital B 1/4, C 1/5 and D the rest. How much share did B get in a profit of Rs.2400 ?
A.s. 532
B.s. 600
C.s. 822
D.s. 812
Answer: B.s. 600
Explanation: Let the total amount in the partnership be 'x'.
Then A's share = x/3
B's share = x/4
C's share = x/5
D's share = x - (x/3 + x/4 +x/5) = 13x/60
A : B : C : D = x/3 : x/4 : x/5 : 13x/60 = 20 : 15 : 12 : 13
B's share in the profit of Rs. 2400 = 15 (2400/60) = Rs. 600.
Answer: B
Question: A and B can do a piece of work in 4 days. B and C can do it in 12 days and A and C in 16 days. Working together they will complete the work in how many days?
A.4.05 days
B.5.05 days
C.14.76 days
D.8.05 days
Answer: B.5.05 days
Explanation: A + B = 1/4
B + C = 1/12
C + A = 1/16
-------------------------------
2(A + B +C) = 1/4 + 1/12 + 1/16 = 19/48
A + B +C = 19/96
96/19 = 5.05 days
ANSWER:B
Question: In a street, there are certain number of houses. People in that street are decided to paint their houses with certain colours. If four houses are painted with each colour, then one house will be left without any colour. If five houses are painted with each colour, then one colour will remain. Find the number of houses in that street?
A.6
B.36
C.25
D.7
Answer: C.25
Explanation: on the basis of question
x = 4y+1
x = 5(y-1)
on solving these 2 equations x = 25
ANSWER:C
Question: There are 5 bags three of which each contains 4 white and 2 black balls, and remaining 2 bags each contains 1 white and 4 black ball; a black ball has been drawn, find the chance that it came from first group.
A.2/7
B.6/35
C.8/25
D.5/13
Answer: D.5/13
Explanation: Please go through my solution and suggest any mistake.
Chances of selecting a black ball from group 1: 1/3----------------------Chances of selecting a black ball from group 2: 4/5
Thus combined probability of section of black ball from group 1:
3/5 x 1/3 = 1/5
Thus combined probability of section of black ball from group 2:
2/5 x 4/5 = 8/25
Out of these chances, chance of occurrence of first case : (1/5) / (1/5 + 8/25) = 5/13
D
Question: The total of the ages of Amar, Akbar and Anthony is 56 years. What was the total of their ages three years ago ?
A.71
B.47
C.66
D.16
Answer: B.47
Explanation: Explanation:
Required sum = (56 - 3 x 3) years = (56 - 9) years = 47 years.
Answer: B
Question: A man can row upstream at 10kmph and downstream at 20kmph. Find the rate of current ?
A.10km/hr
B.15km/hr
C.20km/hr
D.5km/hr
Answer: D.5km/hr
Explanation: Rate of current = 1/2 (20-10) = 5km/hr
Answer is D
Question: The price of a Maruti car rises by 30% while the sales of the car come down by 20%. What is the percentage change in the total revenue?
A.-4%
B.-2%
C.+4%
D.+2%
Answer: C.+4%
Explanation: Explanation :
Let initial price of Maruti car be Rs. 100.
As price increases 30%, the price of car become 100 + 30% of 100 = Rs. 130.
Due to increase in price, sales is down by 20 %.
It means, it is going to make 20% less revenue as expected after increment of price.
So, new revenue = 130 - 20 % of 130 = Rs 104.
The initial revenue was Rs 100 which becomess Rs 104 at the end.
It means there is 4% increment in the total revenue.
Answer : C
Question: A person travels from P to Q a speed of 40 km/hr and returns by increasing his speed by 50%. What is his average speed for both the trips?
A.37
B.26
C.48
D.21
Answer: C.48
Explanation: Speed on return trip = 150% of 40 = 60 km/hr.
Average speed = (2 * 40 * 60)/(40 + 60)
= 48 km/hr.
Answer:C
Question: A cricketer whose bowling average is 12.4 runs per wicket takes 5 wickets for 26 runs and there by decreases his average by 0.4. The number age of the family now is?
A.17
B.98
C.88
D.85
Answer: D.85
Explanation: Let the number of wickets taken till the last match be x. Then,
(12.4x + 26)/(x + 5) = 12
= 12.4x + 26 = 12x + 60
= 0.4x = 34
= x = 340/4 = 85.
Answer: D
Question: If two balls are randomly selected from a green urn containing 9 black and 9 white balls and placed into a yellow urn initially containing 5 black and 3 white balls. What is the probability that the yellow urn will contain an equal number of black and white balls after the change?
A.A.2/9
B.B.4/9
C.C.4/17
D.D.1/3
Answer: C.C.4/17
Explanation: To have equal number of black and white balls, the yellow urn must have 5 black and 5 white balls. So the balls we select out of the green urn must be both white.
Probability (first ball is white) = 9/18
Probability(second ball is white) = 8/17
Probability (both balls are white) = (9/18)*(8/17) = 4/17
Answer C
Question: -24x29+36=?
A.2436
B.2801
C.-2801
D.-660
Answer: D.-660
Explanation: Given exp.=-24x(30-1)+36
=-(24x30)+24+36
=-720+60
=-660
Answer is D
Question: The ratio of the present ages of Sunita and Vinita is 4:5. Six years hence the ratio of their ages will be 14:17. What will be the ratio of their ages 12 years hence?
A.3
B.4
C.5
D.1
Answer: A.3
Explanation: Explanation:
Present age sunita : vinita = 4 : 5
Let their age is 4x and 5x respectively..
After 6 yrs their age ratio will be 14 : 17
Therefore 4x+65x+6=14174x+65x+6=1417
⇒ x = 9
Therefore their present ages are 36,45 respectively.
After 12 yrs their ages will be 48, 57 respectively.
⇒ Ratio after 12 years will be 48: 57 = 16: 19 = 16 : 19
Answer: A
Question: Of the female students at Barkely University, 5/6 are on the honor roll. Of the male students, 2/3 are on the honor roll. If 3/5 of the students are female, what is ratio of male to female students on honor roll?
A.5/9
B.8/15
C.23/30
D.43/60
Answer: B.8/15
Explanation: let the total students be 30
given 3/5 of the students are females = 18
then males = 2/5 = 12
5/6 of the females are on honor roll = 15
males on the honor roll = 2/3= 8
ratio of M:F students on honor roll = 8/15
B
Question: If 7 men and 2 boys working together, can do six times as much work per hour as a man and a boy together. Find the ratio of the work done by a man and that of a boy for a given time?
A.2:5
B.2:3
C.1:8
D.4:1
Answer: D.4:1
Explanation: 7M + 2B = 6(1M + 1B)
7M + 2B = 6M + 6B
1M = 4B
The required ratio of work done by a man and a boy = 4:1
Answer:D
Question: Worker A takes 8 hours to do a job. Worker B takes 10 hours to do the same job. How long it take both A & B, working together but independently, to do the same job?
A.40/9 days
B.20/9 days
C.30/9 days
D.60/9 days
Answer: A.40/9 days
Explanation: A's one hour work = 1/8.
B's one hour work = 1/10.
(A+B)'s one hour work = 1/8+1/10 = 9/40.
Both A & B can finish the work in 40/9 days
Answer : A
Question: The compound interest on $2000 at 10% per annum is $662. The period(in years) is?
A.2
B.3
C.4
D.5
Answer: B.3
Explanation: A = P(1 + R/100)^T
2662 = 2000(1 + 10/100)^T
(11/10)^T = 2662/2000
(11/10)^T = (11/10)^3
T = 3 years
Answer is B
Question: 45 men can complete a work in 19 days. Six days after they started working, 30 more men joined them. How many days will they now take to complete the remaining work?
A.6.2
B.10
C.15
D.7.8
Answer: D.7.8
Explanation: 45*19 men can complete the work in 1 day
1 man's 1 day work = 1/855
45 men 6days work = 6*1/19 =6/19
remaining work = 1-6/19 = 13/19
75 men's 1 day's work = 75/855 = 5/57
13/19 work is done by them in 57/5 * 13/19 = 7.8days
Answer is D
Question: A,B and C are employed to do apiece of work for Rs.529. A and C are supposed to finish 19/23 of the work together. How much shall be paid to B?
A.10
B.11
C.12
D.14
Answer: C.12
Explanation: C
12
12 men can complete a work in 18 days. Six days after they started working, 4 more men joined them. How many days will all of them together complete the remaining work?
Question: A 40-liter solution of alcohol and water is 5 percent alcohol. If 4.5 liters of alcohol and 5.5 liters of water are added to this solution, what percent of the solution produced is alcohol?
A.7%
B.10%
C.13%
D.16%
Answer: C.13%
Explanation: The percent of alcohol in the solution is (0.05(40) + 4.5) / 50 = 6.5/50 = 13%
The answer is C.
Question: A Bus 125 m long passes a man, running at 5 km/hr in the same direction in which the bus is going, in 10 seconds. The speed of the bus is:
A.100 km/hr
B.50 km/hr
C.55 km/hr
D.60 km/hr
Answer: B.50 km/hr
Explanation: speed = 125/10=25/2
==>25/2*18/5
==>45 km/hr
speed of bus x km/hr
x-5 km/hr ==> 45
x = 50 km/hr
ANSWER B
Question: Jim walks 3.3 mph and wants to walk to Dales house that's 3.5 miles away. How long will it take him to get there?
A.78 minutes approx
B.61 minutes approx
C.34 minutes approx
D.1 hr 6 m approx
Answer: D.1 hr 6 m approx
Explanation: 3.5/3.3= 1 hr 6 mins approx
Correct answer D
Question: A man can row 30 km downstream and 20 km upstream in 4 hours. He can row 45 km downstream and 40 km upstream in 7 hours. Find the speed of man in still water?
A.12.8 kmph
B.32.5 kmph
C.18.5 kmph
D.12.5 kmph
Answer: D.12.5 kmph
Explanation: Let the speed of the man in still water be a kmph and let the speed of the stream be b kmph.
Now 30/(a + b) + 20/(a - b) = 4 and 45/(a + b) + 40/(a - b) = 7
Solving the equation, the speed of man in still water is 12.5 kmph.
Answer:D
Question: A class of students appeared in two different tests of quantitative ability both of which were scored out of 100. The scores of each student in each test could be expressed as a product of two distinct prime numbers. If a student’s scores in the two tests did not have any common prime factors, what is the maximum possible difference between his two scores?
A.79
B.83
C.88
D.89
Answer: D.89
Explanation: I started by listing out the primes
2,3,5,7,11,13,17,19,23,29,31,37
Then I tried to maximize the score--we know the minimum score will be 6 as the product has to be between two distinct primes.
Our max score is 100 so lets try to get as close to 100 as possible. 19*5=95
95-6=89
ANSWER:D
Question: 5 coins are tossed together. What is the probability of getting exactly 2 heads?
A.10
B.5/16
C.3/16
D.7/16
Answer: B.5/16
Explanation: Since 5 coins are tossed, sample space = 20/2=10
Getting exactly 2 heads=32
p(E) = 20/32=5/16
ANSWER:B
Question: A sum of money at simple interest amounts to Rs. 820 in 3 years and to Rs. 854 in 4 years. The sum is:
A.500
B.718
C.780
D.910
Answer: B.718
Explanation: Sol.
S.I. for 1 year = Rs. (854 - 820) = Rs. 34.
S.I. for 3 years = Rs. (34 * 3) = Rs. 102.
âˆ´ Principal = Rs. (820 - 102) = Rs. 718
Answer B
Question: Rs.525 among A, B and C such that B may get 2/3 of A and C together get. Find the share of C?
A.228
B.150
C.992
D.277
Answer: B.150
Explanation: A+B+C = 590
5A = 6B = 8C = x
A:B:C = 1/5:1/6:1/8
= 24:20:15
15/59 * 590 = Rs.150
Answer: B
Question: The average score of a cricketer in 2 matches is 60 and in other 3 matches is 50. Then find the average score in all the 5 matches?
A.54
B.27
C.30
D.35
Answer: A.54
Explanation: Average in 5 matches = (2*60 + 3*50)/2+3 = 120+150/ 5 = 270/5 = 54
Answer is A
Question: In how many ways can the letters of wordELECTRICALbe arranged such that all the Consonants always appear together?
A.9!
B.5!*4!
C.5!*6!
D.5!*4!*2!
Answer: C.5!*6!
Explanation: Let the arrangment be: _ _ _ _ _ _ _ _ _ _ (10 letters, 4 vowels E, E, I, A and 6 consonant L, C, T, R, C, L)
For all consonants together, consider them as 1 group {L, C, T, R, C, L} E E I A --> this gives us 5! arrangements with {} group considered as 1 . Now {} group can in itself be arranged in 6! ways
Thus total arrangements with all consonants together = 5!*6! --> C is the correct answer.
Question: The mean of 50 observations was 36. It was found later that an observation 48 was wrongly taken as 21. The corrected new mean is :
A.36.54
B.36.58
C.36.23
D.36.14
Answer: A.36.54
Explanation: Explanation:
Correct Sum = (36 * 50 + 48 - 21) = 1827.
Correct mean = = 1827/50 = 36.54
Answer: A) 36.54
Question: 23 people are there, they are shaking hands together, How many hand shakes possible, if they are in pair of cyclic sequence ?
A.20
B.77
C.66
D.88
Answer: A.20
Explanation: Answer:A
Question: The weight of a hollow sphere is directly dependent on its surface area. The surface area of a sphere is 4π·R^2, where R is the radius of the sphere. If a hollow sphere of radius 0.15 cm made of a certain metal weighs 8 grams, a hollow sphere of radius 0.3 cm made of the same metal would weigh how many grams R?
A.16
B.R=32
C.R=64
D.128
Answer: B.R=32
Explanation: Weight directly proportional to 4 pi r^2
Now, 4pi is constant, so, weight is directly proportional to r^2.
When radius = 0.15, weight = 8, so (0.15) ^ 2 proportional to 8;
(0.15)^2 * 4 proportional to 8*4, solving further
(0.15)^2 * 2 ^2 = (0.15*2)^2 = 0.3 ^ 2; so answer = 32 (B)
Question: A broker invested her own money in the stock market. During the first year, she increased her stock market wealth by 60 percent. In the second year, largely as a result of a slump in the stock market, she suffered a 30 percent decrease in the value of her stock investments. What was the net increase or decrease on her overall stock investment wealth by the end of the second year?
A.−5%
B.5%
C.12%
D.20%
Answer: C.12%
Explanation: The actual answer is obtained by multiplying 160% by 70% and subtracting 100% from this total. That is: 160% × 70% = 112%; 112% − 100% = 12%.
Answer: C
Question: The average age of seven persons sitting in a row facing east is 28 years. If the average age of the first three persons is 25 years and the average age of the last three persons is 32 years, then find the age of the person sitting in the middle of the row?
A.9 years
B.29 years
C.25 years
D.19 years
Answer: C.25 years
Explanation: Total age seven persons = (28 * 7)years
Total age of the first three persons and the last three persons are (25 * 3) years and (32 * 3) years respectively.
Age of the person sitting in the middle of the row = 28 * 7 - 25 * 3 - 32 * 3 = 196 - 75 - 96 = 25 years.
ANSWER:C