Question

SINGLE ANSWER MCQ Q2. The sum of the present ages of a father and son is 70 years. If after 10 years, the ratio of their ages will be 2: 1, and then what is the present age of the son?​

Answer 1

Step-by-step explanation:

let the present age of father be ‘x' and that of son be ‘y'

by the 1st condition,

x + y = 70 ---------( 1 )

By the 2nd condition,

$\frac{x \: + 10}{y + 10} = \frac{2}{1}$

therefore, x + 10 = 2y + 20

x - 2y = 10 --------( 2 )

Adding equation ( 1 ) and ( 2 ) we get ,

y = 60

using y = 60 in equation ( 1 )

x + 60 = 70

x = 10

therefore present age of son is 10 .