Problema Solution

a and b together can do a piece of work in 3 3/7 days. after working 1 day, a left and b finished the work alone in 4 days. how many days will require each of them to do work alone?

Answer provided by our tutors

Amount of work done by 'a' and 'b' in 1 day = 1/(3 3/7) =1/(24/7) = 7/24


Remaining work 1 – 7/24 = 17/24


'b' completes 17/24 work in 4 days


Amount of work 'b' can do in 1 day = (17/24)/4 = 17/4*24 = 17/96


=> 'b' can complete the work in 96/17 days


'a' completes the work in (7/24 - 17/96)^(-1) = 96/11 days (since 1/(amount of work done by a in 1 day) + 1/(amount of work done by / in 1 day) = 7/24)


'a' can complete the work in 96/11 = 8 8/11 days = 8.73 days approximately.


'b' can complete the work in 96/17 = 5 11/17 days = 5.65 days approximately.