The present age of a mother and daughter is in the ratio of 8 : 3. After 12 years, the ratio of their ages will be 2 : 1. What is the sum of the present age of the mother and the daughter?

Let the age of the mother be 8x, and that of the daughter be 3x( since their ages are in the ratio 8:3)

After 12 years, their ages will be (8x + 12) and (3x +12) respectively, which will be in the ratio 2:1.

Therefore, $$\frac{(8x+12)}{(3x+12)} = \frac{2}{1}$$

On cross multiplying we get;

8x + 12 = 6x + 24

2x = 12

x=6.

So, the mother is currently (8×6) 48 years old,and the daughter is (3×6) 18 years old. Therefore, the sum in their ages is 48+18=66years.