AVERAGE AND AGES (QUANTITATIVE APTITUDE) EPFO UPSC

Total Questions: 30

1. The average of five numbers is 281. The average of the first two numbers is 280 and the average of the last two numbers is 178.5. What is the third number ?

Correct Answer: (a) 488 
Solution:

2. The average age of 3 friends is 32 years. If the age of a fourth friend is added, their average age comes to 31 years. What is the age of the fourth friend ?

Correct Answer: (b) 28 years
Solution:

3. Find the average of the following set of scores.

965, 362, 189, 248, 461, 825, 524, 234

Correct Answer: (a) 476 
Solution:

4. If the value of 21a + 21b = 1134, what is the average of a + b?

Correct Answer: (b) 27
Solution:

5. Average weight of three boys P, T and R is 54⅓ kgs while the average weight of three boys, E, F and G is 53 kgs. What is the average weight of P, T, R, E, F and G?

Correct Answer: (d) None of these
Solution:

6. The average of 5 consecutive even numbers A, B, C, D and E is 52. What is the product of B and E?

Correct Answer: (d) 2800
Solution:

7. The average weight of a group of 75 girls was calculated as 47 kgs. It was later discovered that the weight of one of the girls was read as 45 kgs, whereas her actual weight was 25 kgs. What is the actual average weight of the group of 75 girls? (Rounded off to two digits after decimal)

Correct Answer: (a) 46.73 kgs. 
Solution:

8. The total of the ages of a class of 75 girls is 1050, the average age of 25 of them is 12 years and that of another 25 is 16 years. Find the average age of the remaining girls.

Correct Answer: (c) 14 years
Solution:

9. The average of the first 100 positive integers is

Correct Answer: (c) 50.5
Solution:

10. In a family, the average age of a father and a mother is 35 years. The average age of the father, mother and their only son is 27 years. What is the age of the son ?

Correct Answer: (b) 11 years
Solution: