Question

A,B and C a working together can do a piece of work in 8 hours. A alone can do it 20 hours and B alone can do it 24 hours. In how many hours will C alone do it the same work.

Answer 1

Answer:

12.6 hrs

Step-by-step explanation:

Answer:

A,B and C can do a piece of work in 8 hrs.

therefore,part of work done by them in 1 hr = 1/8

A can do the work in  20 hrs

therefore,part of work done by A in 1 hr = 1/20

B can  do the work in 24 hrs

therefore,part of work done by them in 1 hr = 1/24

therefore,part of work done by them in 1 hr = 1/20+1/24 = 11/120

therefore,part of work done by C in 1 hr = 1/8-11/120 =19/240

hence,C can complete the work in 12.6 hrs