Question

A man can do a piece of work in 5 days, but with the help of his son, he can do it in 3 days. In what time can his son do it alone?

• A. 13/2 days
• B. 7 days
• C. 5 days
• D. 8 days
• E. 15/2 days

Answer 1

The correct option is E

15/2 days

Son’s 1 day’s work = $(\frac{1}{3}-\frac{1}{5})=\frac{2}{15}$

$\therefore$ The son alone can do the work in $\frac{15}{2}=7\frac{1}{2}$ days