Question

Arun and vinay together can do a piece of work in 7 days. if arun does twice as much work as vinay, how much days will arun take to complete alone

Answer 1

Acc to the question, Arun and Vinay together can do a piece of work in 7 days.

1/7 = 1/a + 1/v; where a and v are the number of days Arun and Vinay takes to complete the work alone respectively.

Arun does twice as much work as Vinay i.e. 1/7 = 1/v + 2/v

or, v = 21 i.e. Vinay takes 21 days alone.

∵So, Arun will take half the time i.e. 10 days 12 hours.   [21/2 days = 10.5 days]