Question

A and B can do a piece of work in 12 days, C and A in 20 days and B and C in 15 days then in how many days will they
finish it working together​

Answer 1

10day

total work=60

1/12+1/20+1/15=12/60

here 12unit represent a,b,and c work so we devide. by 2

=12/2

=6

= 60/6

=10