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A piece of work can finish by a certain number of men in 100 days. If however, there were 10 men less, it would take 10 days more for the work to be finished. How many men were there originally?

A piece of work can finish by a certain number of men in 100 days. If  however, there were 10 men less, it would take 10 days more for the work to be finished. How many men were there originally?

            a)75                 b)82                 c)100               d)110

























 Expl: Originally let there be x men.

      Less men, more days (Indirect)

      :. (x-10): x : : 100 :110 or x-10/x = 100/110

     or 11x-110 = 10x or x =110

     So, originally there were 110 men.

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