Question

A and B together can do a piece of work in 12 days.while B alone can finish it in 30 days. In how many days can A
alone finish the work

Answer 1

a and b one day work =1/12
b can do alone one day work=1/30
a one day work=1/12-1/30=5-2/60=3/60=1/20
a can alone 1/1/20=20