Question

The ratio of the present age of mother and daughter is 3:1. Six years ago the ratio of their age was 6 : 1. Find their present age.​

Answer 1

30 and 10

Explanation:

Given ratio of age = 3 : 1 = 3x : x ( x is a multiplier )

Six years ago their age ratio was

3x - 6 : x - 6 = 6 : 1 ← express in fractional form

`(3x-6)/(x-6)` =
`(6)/(1)` ( cross- multiply )

6(x - 6) =3 x - 6

6x - 36 = 3x - 6 ( subtract 3x from both sides )

3x - 36 = - 6 ( add 36 to both sides )

3x = 30 ( divide both sides by 3 )

x = 10

Thus their present ages are

mother = 3x = 3 × 10 = 30

daughter = x = 10