Question

a contractor without work force of 400 20 men can complete a work of construction of a building in 9 months due to request by the owners he was asked the to complete the job in 7 month how many extra men he must employ to complete the job ​

Answer 1

9 months :  420 mens

7 months :    x

we have to do cross multiplication then you will get  like this ( given below)

9x = 420 * 7

x =    420 * 7

       --------------

             9

when you cancel 9 and 420 then you will be

140 * 7

-----------

    3

your answer would be = 326.6

Answer 2

Let work to be done be x

Time taken by 420 persons to complete the work. x= 9 months

x= 420×9 = 3780

People required to complete the work in 9 months= x÷7= 3780÷ 7

3780÷7 = 540

Therefore, the contractor had to employ 540 people more to complete the job.

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