1
Rs. 1,600 is divided between Ali and Sara in the ratio 3 : 5. What is Ali’s share?
Correct answer: A. Rs. 600
Total parts = 8. Ali’s share = (3 ÷ 8) × 1,600 = Rs. 600.
easy
Ratio, Average and Ages MCQs
Solved Ratio, Average and Ages MCQs with step-by-step solutions: proportions, averages, average speed and age problems for competitive exams.
23 MCQsUpdated 27 October 2026
This set covers dividing amounts in a ratio, proportion, averages including average speed, and age problems that compare people's ages now, in the past and in the future.
For age questions, set up one equation for the present ages and adjust for "years ago" or "years later". For average speed over equal distances, remember it is not the simple average of the two speeds.
- 2
The ratio 45 : 60 in its simplest form is:
Correct answer: A. 3 : 4
Divide both terms by their HCF, 15: 45 ÷ 15 = 3 and 60 ÷ 15 = 4.
easy - 3
In a class of 35 students, the ratio of girls to boys is 2 : 3. How many girls are there?
Correct answer: D. 14
Total parts = 5. Girls = (2 ÷ 5) × 35 = 14.
easy - 4
If 4 : 9 = 12 : x, what is x?
Correct answer: D. 27
Cross-multiply: 4x = 12 × 9 = 108, so x = 108 ÷ 4 = 27.
easy - 5
If A : B = 2 : 3 and B : C = 4 : 5, then A : B : C is:
Correct answer: C. 8 : 12 : 15
Make B equal in both ratios (LCM of 3 and 4 is 12): A : B = 8 : 12 and B : C = 12 : 15, so A : B : C = 8 : 12 : 15.
medium - 6
What is the average of 12, 15, 18, 21 and 24?
Correct answer: D. 18
Sum = 90. Average = 90 ÷ 5 = 18.
easy - 7
What is the average of the first 10 natural numbers?
Correct answer: C. 5.5
Sum of 1 to 10 = 55. Average = 55 ÷ 10 = 5.5.
easy - 8
The average of 5 numbers is 40. When a sixth number is added, the average becomes 42. What is the sixth number?
Correct answer: A. 52
Sum of 5 numbers = 200. Sum of 6 numbers = 6 × 42 = 252. Sixth number = 252 − 200 = 52.
medium - 9
In a test, 30 students averaged 60 marks and 20 students averaged 80 marks. What is the average of all 50 students?
Correct answer: C. 68
Total marks = 30 × 60 + 20 × 80 = 1,800 + 1,600 = 3,400. Average = 3,400 ÷ 50 = 68.
medium - 10
A car goes from A to B at 40 km/h and returns at 60 km/h. What is its average speed for the whole trip?
Correct answer: C. 48 km/h
For equal distances, average speed = 2 × 40 × 60 ÷ (40 + 60) = 4,800 ÷ 100 = 48 km/h, not the simple average 50.
hard - 11
The average temperature for a week (7 days) was 30°C. The average for the first 6 days was 31°C. What was the temperature on the 7th day?
Correct answer: D. 24°C
Weekly total = 7 × 30 = 210. First 6 days = 6 × 31 = 186. Seventh day = 210 − 186 = 24°C.
medium - 12
A father is three times as old as his son. The sum of their ages is 48 years. What is the son’s age?
Correct answer: B. 12 years
Let the son be x, the father 3x. Then 4x = 48, so x = 12 years.
easy - 13
Ahmed is 5 years older than Bilal. Five years ago, Ahmed was twice as old as Bilal. How old is Ahmed now?
Correct answer: C. 15 years
Let Bilal = b, Ahmed = b + 5. Five years ago: b = 2(b − 5), so b = 10. Ahmed = 10 + 5 = 15 years.
medium - 14
The present ages of A and B are in the ratio 4 : 5. After 6 years, the ratio will be 5 : 6. What is A’s present age?
Correct answer: D. 24 years
Let ages be 4x and 5x. (4x + 6) ÷ (5x + 6) = 5 ÷ 6 gives 24x + 36 = 25x + 30, so x = 6. A = 4 × 6 = 24 years.
hard - 15
The average age of a husband, wife and their child 3 years ago was 27 years. The average age of the wife and child 5 years ago was 20 years. What is the husband’s present age?
Correct answer: B. 40 years
Present total of all three = (27 + 3) × 3 = 90. Present total of wife and child = (20 + 5) × 2 = 50. Husband = 90 − 50 = 40 years.
Read detailshard - 16
If 5 workers earn Rs. 7,000 in a day, how much do 7 workers earn at the same rate?
Correct answer: C. Rs. 9,800
One worker earns 7,000 ÷ 5 = 1,400. Seven workers earn 7 × 1,400 = Rs. 9,800.
easy - 17
Two numbers are in the ratio 5 : 7 and their difference is 18. What is the larger number?
Correct answer: C. 63
Difference of parts = 7 − 5 = 2 parts = 18, so 1 part = 9. Larger number = 7 × 9 = 63.
medium - 18
The mean proportional between 4 and 16 is:
Correct answer: D. 8
Mean proportional = √(4 × 16) = √64 = 8.
medium - 19
Zara scored 72, 85, 64, 90 and 79 in five subjects. What is her average score?
Correct answer: D. 78
Total = 390. Average = 390 ÷ 5 = 78.
easy - 20
The average of 4 consecutive even numbers is 27. What is the largest of these numbers?
Correct answer: C. 30
Four consecutive even numbers centred on 27 are 24, 26, 28 and 30. The largest is 30.
medium