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It takes 10 days for digging a trench of 100 m long, 50 m broad and 10 m deep. What length of trench, 25 m broad and 15 m deep can be dug in 30 days ?

 It takes 10 days for digging a trench of 100 m long, 50 m broad and 10 m deep.  What length of trench, 25 m broad and 15 m deep can be dug in 30 days ?

      a) 400 m          b) 200 m          c) 100 m          d) 89m
























Expl : More days, more length (Direct)

      Less breadth, more length (Indirect)

      More depth, less length (Indirect

      Days      10 : 30;

      Breadth  25 : 50;                  : : 100 : x

      Depth    15 : 10;              



      :. 10 * 25* 15 * x = 30 *50 * 10 *100

            x= (30*50*10*100)/10*25*15 = 400

     So the required length = 400m

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