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 ?
Choose the correct choice from the following choices:
A) 13/2  B) 19/2  C) 21/2  D) 15/2  E) None
Son's one day work = (1/3âˆ’1/5)=2/15   So son will do whole work in = 15/2 days   Answer: 21/2
<result>C</result>
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 ?