Question

9.
A and B together can finish a piece of work in 12 days. If ' A'alone can finish the same
work in 20days, in how many days B alone can finish it?​

Answer 1

Answer:

as we know a person one day work is equal to 1/n of total work where n is number of days

therefore a+b is equal to

Va of the total work+1/b of the total work

=1/12(as we calulate per day)

1/20+1/b of the total work =1/20 (as they gave as

a alone can do in 20 days)

Vb of the total work =1/20-1/12

Vb of the total work =as LCM is 60 we get

3-5/60

Vb of the total work=-2/60-1/30

therefore as b one day work is 1/30 the total

work is equal to 30 days

b works in 30 days or in 1 month