RikoteMaster/aqua-rat-mcqa huggingface dataset:
Question: At what time between 4 and 5 o'clock will the hands of a watch point in opposite directions?
A.(54 + 6/11) past 49
B.(54 + 6/11) past 2
C.(54 + 6/11) past 7
D.(54 + 6/11) past 4
Answer: D.(54 + 6/11) past 4
Explanation: 4 o'clock, the hands of the watch are 20 min. spaces apart.
To be in opposite directions, they must be 30 min. spaces apart.
Minute hand will have to gain 50 min. spaces.
55 min. spaces are gained in 60 min
50 min. spaces are gained in min. or
Required time = min. past 4.
Answer: D)
Question: In a garden, 26 trees are planted at equal distances along a yard 300 metres long, one tree being at each end of the yard. What is the distance between two consecutive trees?
A.10 metres
B.20 metres
C.14 metres
D.12 metres
Answer: D.12 metres
Explanation: Between 26 trees, there are 25 gaps
Length of each gap
=300/25
=12
i.e., distance between two consecutive trees =12
Answer: D
Question: The C.P of 20 books is equal to the S.P of 30 books. Find his gain% or loss%?
A.63.33%
B.34.33%
C.33.33%
D.31.33%
Answer: C.33.33%
Explanation: explanation:
20 CP = 30 SP
30 --- 10 CP loss
100 --- ? => 33.33% loss
Answer: C
Question: Look at this series: 544, 509, 474, 439, ... What number should come next?
A.404
B.414
C.420
D.445
Answer: A.404
Explanation: Explanation: This is a simple subtraction series. Each number is 35 less than the previous number.
Answer: Option A
Question: A car started running at a speed of 30 km/hr and the speed of the car was increased by 2 km/hr at the end of every hour. Find the total distance covered by the car in the first 9 hours of the journey.
A.342 km
B.352 km
C.642 km
D.742 km
Answer: A.342 km
Explanation: The total distance covered by the car in the first 10 hours = 30 + 32 + 34 + 36 + 38 + 40 + 42 + 44 + 46 = sum of 10 terms in AP whose first term is 30 and last term is 46 = 9/2 [30 + 46] = 342 km.
ANSWER:A
Question: Two pipes A and B can fill a tank in 12 and 24 minutes respectively. If both the pipes are used together, then how long will it take to fill the tank?
A.9 min
B.8 min
C.6 min
D.4 min
Answer: B.8 min
Explanation: Explanation:
Required time =12×24 / 12+24
=12 x 24/36
=24/3 = 8 minutes
Answer: Option B
Question: Two pipes A and B can fill a cistern in 37 1/2 minutes and 45 minutes respectively. Both pipes are opened. The cistern will be filled in just half an hour, if the pipe B is turned off after?
A.6
B.9
C.8
D.2
Answer: B.9
Explanation: Let B be turned off after x minutes. Then, part filled by (A + B) in x min + part filled by A in (30 - x) min = 1.
x(2/75 + 1/45) + (30- x) 2/75 = 1
11x + 180 - 6x = 225 => x = 9.Answer:B
Question: There 3 kinds of books in the library physics, chemistry and biology. Ratio of physics to chemistry is 3 to 2; ratio of chemistry to biology is 4 to 3, and the total of the books is more than 3000. Which one of following can be the total Q of the book?
A.3003
B.3027
C.3024
D.3021
Answer: A.3003
Explanation: First, you have to find the common ratio for all 3 books. You have:
P:C:B
3:2 --> multiply by 2 (gives you row 3)
4:6
6:4:3
Hence:
P:C:B:T(Total)=Q
6:4:3:13 ----> This means, the Total Number must be a multiple of 13.
Answer A is correct since 299 is divisible by 13, hence is 2990 and so is 3003 (2990+13).
Question: In a triangle, one side is 6 Cm and another side is 8 Cm. which of the following can be the perimeter of the triangle?
A.22.
B.25.
C.30.
D.32.
Answer: A.22.
Explanation: Given : one side is 6 Cm and another side is 8 Cm. So the 3rd side will be > 3 and < 15. Thus the perimeter will be : 18 < perimeter < 30. Only option satisfying this condition is 22. Hence A.
Question: In a box, there are 6 blue, 7 white and 4 yellow bulbs. One bulb is picked up randomly. What is the probability that it is neither white nor blue?
A.3/16
B.5/16
C.8/32
D.4/17
Answer: D.4/17
Explanation: Total number of bulbs = (6 + 7 + 4) = 17.
Let E = event that the bulb drawn is neither white nor blue = event that the bulb drawn is yellow.
Therefore, P(E)=4/17
ANSWER:D
Question: The length of the bridge, which a train 120 metres long and travelling at 45 km/hr can cross in 30 seconds, is?
A.10 m
B.255 m
C.245 m
D.19 m
Answer: B.255 m
Explanation: Speed = [45 X 5/18] m/sec = [25/2] m/sec Time = 30 sec Let the length of bridge be x metres. Then, (120 + x)/30
= 25/2 => 2(120 + x) = 750 => x
= 255 m.
Answer: B
Question: A frog jumps 3 ft comes back 2ft in a day. In how many days it will come out of 30ft deep well
A.27
B.28
C.29
D.30
Answer: B.28
Explanation: A frog jumps 3ft in day and comes back 2ft in night.in how many days it will come out of 30ft deep well?
(3-2)*27 +3*1
total days=28
ANSWER:B
Question: The average runs scored by a batsman in 10 matches is 40. In the next 10 matches the batsman scored an average of 30 runs. Find his average in all the 20 matches?
A.31
B.35
C.88
D.13
Answer: B.35
Explanation: Total score of the batsman in 10 matches = 400.
Total score of the batsman in the next 10 matches = 300.
Total score of the batsman in the 20 matches = 700.
Average score of the batsman = 700/20 = 35.
Answer:B
Question: The length of a rectangle is twice its breadth. If its length is decreased by 4 cm and breadth is increased by 5 cm, the area of the rectangle is increased by 75 sq. cm. Find the length of the rectangle.
A.10/3cm
B.20/3cm
C.20cm
D.16cm
Answer: B.20/3cm
Explanation: Explanation:
Let breadth = x. Then, length = 2x. Then,
(2x - 4) (x + 5) - 2x * x = 75 => 6x - 25 = 75 => x =20/3.
Length of the rectangle = 20/3 cm.
Answer: Option B
Question: Two passenger trains start at the same hour in the day from two different stations and move towards each other at the rate of 13 kmph and 21 kmph respectively. When they meet, it is found that one train has traveled 60 km more than the other one. The distance between the two stations is?
A.477
B.408
C.279
D.276
Answer: B.408
Explanation: 1h ----- 5
? ------ 60
12 h
RS = 13 + 21 = 34
T = 12
D = 34 * 12 = 408.Answer: B
Question: For a certain exam,a score of 86 was 7 standard deviations below mean and a score of 90 was 3 standard deviations above mean.What was the mean score for the exam?
A.86.25
B.84
C.85
D.88.8
Answer: D.88.8
Explanation: Mean-7SD=86
Mean+3SD=90
By solving above equations we get,
SD (absolute value)=0.4
Mean=88.8
ANS. D
Question: A store sells chairs and tables. If the price of 2 chairs and 1 table is 60% of the price of 1 chair and 2 tables, and the price of 1 table and 1 chair is $60, what is the price, in dollars, of 1 table? (Assume that every chair has the same price and every table has the same price.)
A.105/2
B.45
C.44
D.52
Answer: A.105/2
Explanation: LET C= CHAIR ; T =TABLE
2C+1T = 0.6 (1C + 2T) OR C( 2-0.6) = 1.2T -1T OR 1.4C = 0.2 T THEREFORE C= 0.2/1.4 T = 1/7 T
IC +1T =60 OR 1/7T + 1T =60 THEREFORE T= 60*7/8 = 105/2
A
Question: Which one of the following is not a prime number?
A.31
B.61
C.71
D.91
Answer: D.91
Explanation: 91 is divisible by 7. So, it is not a prime number.
answer :D
Question: Bobby has 23 Pokemon cards and he would like to give four friends his
cards. How many cards will each friend get? Will there be any cards left
over?
A.5 cards-3 left over
B.6 cards-4 left over
C.7 cards-5 left over
D.8 cards-6 left over
Answer: A.5 cards-3 left over
Explanation: 23/4 = 5 R 3 Each friend will get 5 cards and there will be 3 cards left
over.
correct answer A
Question: A batsman scored 210 runs which included 3 boundaries and 8 sixes. What % of his total score did he make by running between the wickets
A.40%
B.50%
C.65%
D.71.4%
Answer: D.71.4%
Explanation: Number of runs made by running = 210 - (3 x 4 + 8 x 6)
= 210 - (60)
= 150
Now, we need to calculate 60 is what percent of 120.
=> 150/210 * 100 = 71.4 %
D
Question: Jamshid and Irwin decided to make up their own version of basketball. In addition to being able to score 2-point baskets, they created ways to score 5-, 11-, and 13-point baskets. If at halftime the product of the point values of Irwin’s baskets was 2,420, how many 11-point baskets E did Irwin score?
A.0
B.1
C.2
D.3
Answer: C.2
Explanation: First thing I noticed was that all these numbers are prime...
Prime factorization gives the following
Step 1:2*1210
Step 2:2*11*110
Step 4:2*11*11*10
Step 5:2*11*11*2*5
So he scored E=2 11-point baskets in my opinion.
Answer C
Question: A bakery currently has 9 pies and 2 cakes in its inventory. The bakery’s owner has decided to display 5 of these items in the bakery’s front window. If the items are randomly selected, what is the probability that the display will have exactly 3 pies?
A.3/5
B.4/7
C.5/7
D.2/11
Answer: D.2/11
Explanation: The total number of ways to choose 5 from 11 is 11C5 = 462.
The number of ways that include 3 pies is 9C3*2C2 = 84*1 = 84
P(exactly 3 pies) = 84/462 = 2/11
The answer is D.
Question: David and Rachel are getting married. The extended family wants to have its picture taken, but David's father is unwilling to stand next to Rachel's mother. How many options does the photographer have to arrange the 15 family members in a row for the picture?
A.15!
B.14×13!
C.13×14!
D.14!/2!
Answer: C.13×14!
Explanation: The number of ways to arrange 15 people is 15!
We need to subtract the arrangement when these two people are together.
Let's think of these two people as a single unit so there are 14 units.
The number of ways to arrange 14 units is 14!
We need to multiply this by 2 since these two people could switch places.
The total number of valid arrangements is 15! - 2*14! = 14!*(15-2) = 13x14!
The answer is C.
Question: If two dice are thrown simultaneously, find the probability that the numbers appeared are equal?
A.2/6
B.1/6
C.3/6
D.4/6
Answer: B.1/6
Explanation: The numbers appeared are equal.
Therefore, the required events are (1, 1), (2, 2), (3, 3), (4, 4), (5, 5) and (6, 6).
Therefore, n(E) = 6
Therefore, the required probability = n(E)/n(S) = 6/36
= 1/6
ANSWER:B
Question: A sum of money becomes triple itself in 5 years at simple interest. How many years will it become four times at the same rate?
A.12 Â½ years
B.62 Â½ years
C.8 Â½ years
D.72 Â½ years
Answer: C.8 Â½ years
Explanation: 100 ---- 200 ---- 5
200 ---- 5
100 ---- 2 1/2
------------------
400 ---- 8 Â½ years
Answer:C
Question: A three-digit code for certain locks uses the digits 0, 1, 2, 3, 4, 5 according to the following constraints. The first digit cannot be 0 or 1, the second digit must be 0 or 1, and the second and third digits cannot both be 0 in the same code. How many different codes are possible?
A.144
B.152
C.160
D.44
Answer: D.44
Explanation: The first digit can be filled in 4 ways
For second digit , it can either be 0 or 1
Case 1 -
If second digit is 1 ,Third digit can take 6 values
number of codes = 4 * 1 * 6 = 24
Case 2 -
If second digit is 0,Third digit can take 5 values ( Third digit can't be zero)
number of codes = 4 * 1 * 5= 20
Total number of codes =44
Answer D
Question: Machine A produces pencils at a constant rate of 9000 pencils per hour, and machine B produces pencils at a constant rate of 7000 pencils per hour. If the two machines to gather must produce 100,000 pencils and if each machine can operate for at most 8 hours, what is the least amount of time E, in hours, that machine B must operate?
A.4
B.4 2/3
C.5 1/3
D.6
Answer: A.4
Explanation: Machine A produces pencils at a constant rate of 9,000 pencils per hour, and machine B produces pencils at a constant rate of 7,000 pencils per hour. If the two machines together must produce 100,000 pencils and if each machine can operate for at most 8 hours, what is the least amount of time E, in hours, that machine B must operate?
a) 4
b) 4 and 2/3
c) 5 and 1/3
d) 6
e) 6 and 1/4
To minimize the time that machine B must operate we must maximize the time machine A can operate, so make it operate 8 hours. In 8 hours machine A will produce 8*9,000=72,000 pencils, so 100,000-72,000=28,000 pencils are left to produce, which can be produced by machine B in 28,000/7,000=4 hours.
Answer: A.
Question: What is the remainder when 12987^(65987036) is divided by 5?
A.0
B.1
C.2
D.3
Answer: B.1
Explanation: We need to find the units digit of the number.
The units digit of powers of seven repeats 7, 9, 3, and 1 cyclically.
Since 65987036 has the form 4a, the units digit is 1.
Then the remainder when dividing by 5 is 1.
The answer is B.
Question: In a factory, each day the expected number of accidents is related to the number of overtime hour by linear equation. Suppose that on one day there were 1000 overtime hours logged and 8 accidents reported and on another day there were 400 overtime hours logged and 5 accidents. What is the expected number of accidents when no overtime hours are logged?
A.2
B.3
C.4
D.5
Answer: B.3
Explanation: Explanation :
Let, the number of over time hours be x and expected number of accidents be y.
We will use the equation y = mx + c , where m and c are constant.
Now,according to the question,
if x =1000, then y=8
i.e 8=1000x + c ----(i)
And, if x=400, then y=5
i.e 5=400x + c. ----(ii)
On solving these equations, we get
m=1/200 and c=3.
Hence, in case, no overtime is there i.e x=0, then the number of expected accident will be 3.
Answer : B
Question: A voltage will influence current only if the circuit is:
A.2
B.7
C.6
D.889
Answer: B.7
Explanation: Answer:B
Question: A typist uses a sheet measuring 20cm by 30cm lengthwise. If a margin of 2 cm is left on each side and a 3 cm margin on top and bottom, then percent of the page used for typing is
A.40
B.60
C.64
D.72
Answer: C.64
Explanation: Solution
Area of the sheet	= (20 x 30 ) cm²
= 600 cm²
Area used for typing	= [(20 - 4) x (30 - 6)] cm²
= 384 cm²
Required percentage	= (384 / 600 x 100)%
=64%.
Answer C
Question: A is two years older than B who is twice as old as C. The total of the ages of A, B and C is 27. How old is B?
A.25
B.20
C.15
D.10
Answer: D.10
Explanation: Let age of C =x. Then,
Age of B =2x
Age of A =2+2x
Total age of A,B and C =27
⇒(2+2x)+2x+x=27⇒5x=25⇒x=255=5
B's age =2x=2×5=10
Answer is D.
Question: A shopkeeper sells his goods at cost price but uses a faulty meter that weighs 940 grams. Find the profit percent.
A.7.38
B.5.38
C.4.38
D.6.38
Answer: D.6.38
Explanation: Explanation:
(100 + g) / (100 + x) = True measure / Faulty measure
x = 0
true measure = 1000
faulty measure = 940
100 + g / 100 + 0 = 1000 / 940
100+g = 100/94*100
g = 6.38
ANSWER: D
Question: The numbers in which of the following pairs do NOT have a pair of distinct prime divisors in common?
A.10 and 20
B.12 and 18
C.24 and 16
D.21 and 63
Answer: C.24 and 16
Explanation: 16 has only the prime 2 (16=2^4) in its prime factorization, so it can not have a PAIR of distinct prime divisors in common with ANY of the numbers.
The answer is C.
Question: Find The Odd One Out ?
A.BACK
B.SNIP
C.TRAP
D.DRAW
Answer: A.BACK
Explanation: A
BACK
All the others can also be read backwards as proper words.
Question: The number of singles that a baseball player hit increased 11 percent from her first season to her second season, and the number of doubles that she hit in the same time period decreased by 1 percent. If the total number of singles and doubles that she hit increased 2 percent from her first season to her second season, what is the ratio of the number of singles she hit in her first season to the number of doubles she hit in her first season?
A.1:3
B.9:11
C.1:1
D.2:1
Answer: A.1:3
Explanation: Soln:-
1.11S + 0.99D = 1.02[S + d]
0.09S = 0.03D
S/D = 1/3
ANSWER:A
Question: The average monthly salary of laborers and supervisors in a factory is Rs.1250 per month; where as the average monthly salary of 6 supervisors is Rs.2450. If the average monthly salary of the laborers is Rs.950 find the number of laborers?
A.12
B.42
C.66
D.88
Answer: B.42
Explanation: 5x 6x 2x
50 25 100
250x + 150x + 200x = 4200
600x = 4200
x = 7 => 6x = 42
Answer: B
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. 1500. The difference between the profit shares of A and C is?
A.288
B.266
C.155
D.600
Answer: D.600
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. 1500
=> 5 parts out of 15 parts is Rs. 1500
Now, required difference is 6 - 4 = 2 parts
Required difference = 2/5 (1500) = Rs. 600
Answer:D
Question: Pipes A and B can fill a tank in 5 and 6 hours respectively. Pipe C can empty it in 12 hours. If all the three pipes are opened together, then the tank will be filled in
A.1×13/17 hours
B.2×8/11 hours
C.3×9/17 hours
D.4×1/2 hours
Answer: C.3×9/17 hours
Explanation: Solution
Net part filled in 1 hour	= (1/5 + 1/6 -1/12)
= 17/60.
Therefore, the tank will be full in 60/17 hrs.	‹=› 3×9/17 hrs.
Answer C
Question: By selling 12 pencils for a rupee a man loses 20%. How many for a rupee should he sell in order to gain 20%?
A.8
B.9
C.12
D.16
Answer: A.8
Explanation: Explanation:
80% --- 12
120% --- ?
80/120 * 12 = 8
ANSWER IS A
Question: Solution X is 10 percent alcohol by volume, and solution Y is 30 percent alcohol by volume. How many milliliters of solution Y must be added to 300 milliliters of solution X to create a solution that is 18 percent alcohol by volume?
A.100
B.150
C.200
D.250
Answer: C.200
Explanation: 18% is 8%-points higher than 10% but 12%-points lower than 30%.
Thus there should be 3 parts of solution X for 2 parts of solution Y.
We should add 200 ml of solution Y.
The answer is C.
Question: Income and expenditure of a person are in the ratio 9 : 8. If the income of the person is Rs. 18000, then find his savings?
A.Rs.3600
B.Rs.3603
C.Rs.2000
D.Rs.3632
Answer: C.Rs.2000
Explanation: Let the income and the expenditure of the person be Rs. 9x and Rs. 8x respectively.
Income, 9x = 18000 => x = 2000
Savings = Income - expenditure = 9x - 8x = x
So, savings = Rs.2000
Answer:C
Question: The cost per pound of tea and milk powder were the same in June. In July, the price of milk powder shot up by 200% and that of tea dropped by 80%. If in July, a mixture containing equal quantities of tea and milk powder costs $4.80 for 3lbs, how much did a pound of tea cost in July?
A.$4
B.$0.2
C.$1
D.$3
Answer: B.$0.2
Explanation: Lets assume price of Coffee in June =100x
Price of Tea in June =100x
Price of milk powder in July = 300x (because of 200% increase in price)
Price of Tea in July = 20x (because of 80% Decrease in price)
Price of 1.5 pound milk powder 1.5 pound of Tea in July will be = 450x + 30x = 480x
As per question
480x= 4.80$
x = 0.01S
So the Price of Tea in July = 20x = 20 x 0.01 = 0.2$/pound
Answer B
Question: If a is the sum of m consecutive positive integers and b is the sum of n consecutive positive integers. For which of the following values of m and n is it impossible that a = b?
A.m = 2; n = 6
B.m = 3; n = 6
C.m = 10; n = 4
D.m = 7; n = 9
Answer: C.m = 10; n = 4
Explanation: I approached this in a different way, although may be longer but it's certainly more intuitive
It is impossible that a = b if one of them is necessarily even while the other is necessarily odd
for two consecutive integers the sum is necessarily odd
for six consecutive integers the sum is necessarily odd (sum of 3two consecutive integerswhich are all odd)
Thus A is incorrect.
The sum of 3 consecutive integers can be even or odd (an odd integer from the first 2 + an additional integer which can be even or odd). Thus B is incorrect. You can do a similar approach for D and E (it follows that the sum of a specified odd number of consecutive integers can be odd or even).
Leaving us with C to be the only not-wrong answer. To confirm, you can easily deduce that the sum of 4 consecutive integers (sum of 2 odd integers) is necessarily even while the sum of 10 consecutive integers (sum of 5 odd integers) is necessarily odd. Thus C is the right answer.
Question: A five digit number is to be formed using each of the digits 1, 2, 3, 4 and 5 ONLY ONCE. How many numbers can be formed when 3 and 4 are not together ?
A. 48
B. 36
C. 60
D. 72
Answer: D. 72
Explanation: Reqd ways = (Total No. of ways - cases when both 3 and 4 are together)
5 numbers can be arranged in 5 places in 5! ways. Now tie 3 and 4 together so effectively there are 4 nos. they can be arranged in 4! ways. 1 and 2 can be arranged within themselves in 2!ways.
Reqd. Answer = 5! - 4!2! = 120 - (24*2) = 72
Answer: D
Question: A car averages 30 miles per hour for the first 6 hours of a trip and averages 46 miles per hour for each additional hour of travel time. If the average speed for the entire trip is 34 miles per hour, how many hours long is the trip?
A.8
B.10
C.12
D.14
Answer: A.8
Explanation: Let T be the total time of the trip.
30*6 + 46(T-6) = 34T
12T = 276-180
T = 8
The answer is A.
Question: A 1100 m long train crosses a tree in 110 sec, how much time will It take to pass a platform 700 m long?
A.288
B.190
C.188
D.180
Answer: D.180
Explanation: L = S*T
S= 1100/110
S= 10 m/Sec.
Total length (D)= 1800 m
T = D/S
T = 1800/10
T = 180 Sec
Answer:D
Question: The area of a square field is 625 km2. How long will it take for a horse to run around at the speed of 25 km/h ?
A.12 h
B.10 h
C.8 h
D.4 h
Answer: D.4 h
Explanation: Explanation Area of field = 625 km2. Then, each side of field = √625=25km Distance covered by the horse = Perimeter of square field = 25 × 4 = 100 km ∴ Time taken by horse = distances/peed=100/25=4h Answer D
Question: For any triangle T in the xy–coordinate plan, the center of T is defined to be the point whose x–coordinate is the average (arithmetic mean) of the x–coordinates of the vertices of T and whose y–coordinate is the average of the y–coordinates of the vertices of T. If a certain triangle has vertices at the points (0,0) and (9,0) and center at the point (3,3), what are the coordinates of the remaining vertex?
A.(3,4)
B.(3,6)
C.(0,9)
D.(6,4)
Answer: C.(0,9)
Explanation: Let (a,b) be the remaining vertex.
x: 0 + 9 + a = 3*3. Then a = 0.
y: 0 + 0 + b = 3*3. Then b = 9.
The answer is C.
Question: The total of the ages of Amar, Akbar and Anthony is 80 years. What was the total of their ages three years ago ?
A.71 years
B.72 years
C.74 years
D.77 years
Answer: A.71 years
Explanation: The total of the ages of Amar, Akbar and Anthony is 80 years.
total of their ages three years ago = 80-3*3= 71 yrs
ANSWER:A
Question: Mangala completes a piece of work in 10 days, Raju completes the same work in 40 days. If both of them work together, then the number of days required to complete the work is?
A.5 days
B.6 days
C.7 days
D.8 days
Answer: D.8 days
Explanation: If A can complete a work in x days and B can complete the same work in y days, then, both
of them together can complete the work in x y/ x+ y days.
That is, the required No. of days = 10 × 40/50 = 8 days.
D)
Question: The number of diagonals of a polygon of n sides is given by the formula z=n(n-3)/2. If a polygon has twice as many diagonals as sides, how many sides does it have?
A. 3
B. 5
C. 6
D. 7
Answer: B. 5
Explanation: z=n(n-3)
z=2*n
2n=n(n-3)
=>2=n-3
=>n=5
Answer B
Question: The ratio of the ages of three people is 4:6:7. Eight years ago, the sum of their ages was 61. Find their present ages.
A.12,18,21
B.16,24,28
C.20,30,35
D.24,36,42
Answer: C.20,30,35
Explanation: Let the present ages be 4x, 6x, 7x.
(4x-8) + (6x-8) + (7x-8) = 61
17x = 85
x = 5
Their present ages are 20, 30, and 35.
The answer is C.