###
**Four years ago, the average age of a family of four persons was 18 years. During this period, a baby was born. Today if the average age of the family is still 18 years, the age of the baby is
**

A. 1.2 years
B. 2 years
C. 2.5 years
D. 3 years
**Answer: Option B**

## Show Answer

Solution(By Apex Team)

Sum of the ages of 4 members, 4 years ago
= (18 × 4) years
= 72 years
Sum of the ages of 4 members now
= (72 + 4 × 4) years
= 88 years
Sum of the ages of 5 members now
= (18 × 5) years
= 90 years
∴ Age of the baby
= (90 – 88) years
= 2 years

## Related Questions On Average

### Ajit has a certain average for 9 innings. In the tenth innings, he scores 100 runs thereby increasing his average19 people went to a hotel for combine dinner party 13 by 8 runs. His new average is:

A. 20B. 21

C. 28

D. 32

### Find the average of all the numbers between 6 and 34 which are divisible by 5.

A. 18B. 20

C. 24

D. 30

### 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?

A. 10 yearsB. 10.5 years

C. 11 years

D. 12 years

### If the arithmetic mean of 0, 5, 4, 3 is a, that of -1, 0, 1, 5, 4, 3 is b and that of 5, 4, 3 is c, then the relation between a, b, and c is.

A. a = b = cB. a : b : c = 3 : 2 : 4

C. 4a = 5b = c

D. a + b + c = 12