Work Rate and Time

Question

a can do a piece of work in 12 hours, b in 6 hours, c in 4 hours. a does the work for 2 hours and then b and c join. how much time does it take for a alone to finish the work?

Can some one pls answer this question?

AmoyV · Answer

Could you revise your question? The question "how much time does it take for A alone to finish work" doesn't seem right considering the type of information given. I guess the question should be "how much time does it take for the work to finish?"

sarthaktuli · Answer

The question is how much time does it take for a alone to finish the remaining work?

AmoyV · Answer

How much time do B and C work on the work? We can't calculate the answer till we are able to deduct the amount of work B and C did from the total work.

sarthaktuli · Answer

How much time do B and C work on the work? We can't calculate the answer till we are able to deduct the amount of work B and C did from the total work.

So basically calculate the amount of time a,b and c can do the remaining work in. Then my question is if a alone were to do that remaining work, how much time would it take a then?

sarthaktuli · Answer

So basically calculate the amount of time a,b and c can do the remaining work in. Then my question is if a alone were to do that remaining work, how much time would it take a then?

AmoyV · Answer

We don't need to make any calculations then. The answer is 12 hours.

For more information refer to the below pasted post:

work-word-problems-made-easy-87357.html

Also, I think you would find this book helpful:
gmat-math-book-in-downloadable-pdf-format-130609.html

SlikRick · Answer

Are you sure the question isn't asking something along the lines of "A works for two hours. Then B and C join. How long does it take A, B, AND C to complete the job?"

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