Question

3. A and B can do a piece of work in 72 days : B and C can do it in 120 days : A and C can do it in 90 d
what time can A, B and C together finished the work?​

Answer 1

Answer:

1/2(1/72+1/120+1/90)

1/2(12/360)

1/2(1/30)

60days