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 the son do it alone...? Mcqs

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 the son do it alone...?

(A) 7.5 days

(B) 6.5 days

(C) 5.5 days

(D) 4.5 days