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Vlada S.

asked • 04/07/17

4 people can dig up a trench in 3 hours. How long will it take 9 people?

Please give the answer in mins

2 Answers By Expert Tutors


Mark M. answered • 04/07/17

5.0 (243)

Mathematics Teacher - NCLB Highly Qualified

J.R. S.

Hey Mark, I'm a chemist, not a mathematician, but shouldnt it take 9 people LESS time to dig the trench than it does 4 people?  When I solve 4t = (3)(9) I get an answer greater than 3 hours.  Is this correct?  Isn't this an inverse relationship?


Mark M.

You are absolutely correct! It is an inverse relationship.
(4)(3) = (9)(h)
12 = 9h
4/3 = h


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