The age of the father 4 years ago was 8 times the age of his son. At present, the father's age is 4 times that of his son. Find the present age of son.

Options

A. 9 years
B. 7 years
C. 14 years
D. 18 years

Answer

B

Explanation

Suppose, the present age of son be x years.
Therefore, the present age of father = 4x years
According to the question, 4 years ago
`8(x-4)=4x-4`
`implies8x-32-4x-4`
`implies8x-4x=32-4`
`implies4x=28`
`:.x=(28)/(4)=7`
Present age of son =7 years