Question

A,B and C can do a work in 12,15 and 20 days respectively.They all work for one day. Then B leaves the group. In how days will Aand and Complete the rest of the work?​

Answer 1

work done by a=12 days

work done by b=15 days

work done by c=20 days

work done by a,b and c=1/12+1/15+1/20

=5/60+4/60+3/60

=12/60

=1/5

total work=1

work done by them in one day=1-1/5

remaining work=4/5

work done by a and c=1/12+1/20

=5/60+3/60

=8/60

=2/15

A.T.Q,

4/5÷2/15

=6 days

the rest of the work will be done in 6 days by a and c.