Question

the average age of a husband and wife was 30yrs, 4yr ago. what will be their average at present?

Answer 1

Answer:

Given that, 4yrs. back, the average age of a couple=25yrs.

Then, the total==25×2yrs.=50yrs.

After 4yrs. the sum will increase by 4×2yrs.=8yrs.

Let the child's age=xyrs.

Then the toal age of the family=(50+8+x)yrs=(58+x)yrs.

Then, by the given condition,

3

58+x

=20

⟹58+x=60

⟹x=2yrs.

Answer 2

Answer:

34

Step-by-step explanation:

Let the age of husband and wife be x and y.

Their age 4 yrs ago is therefore, x-4 and y-4.

Avg of ages(4yrs ago)$=30=\frac{(x-4)+(y-4)}{2}$

Solve the equation to get x+y value

x+y=68

Present avg=$\frac{x+y}{2}$

                    =68/2

                     =34