Age Problem (Basic Algebra)

Question

A person’s present age is two – fifth of the age of his mother. After 8 years he will be one – half of the age of his mother. How old is the mother at present?

Answer 1

P = 2M/5

P+8 = (M+8)/2 = M/2 + 4

P= M/2 -4

2M/5 = M/2 - 4

M/2 - 2M/5 = 4

5M/10 - 4M/10 = 4

M/10 = 4

M = 4x10 = 40 years old