math word problem

Question

If ben spends 1/3 of his time on section A.

1/5 of his time on section B.

And 48 minutes on section C.

How much time did ben take to complete the whole test? 

Answer 1

Let x = total time Ben spent on test

 

     Section A       +      Section B     +   Section C      =    Total time

       (1/3)x         +       (1/5)x         +         48          =        x

 

    5x  + 3x  +   720  =  15x            [multiply equation by 15 to get rid of fractions]

     720 = 7x                                  [collect terms]

     102.86 = x                                  [divide both sides by 7]

       x = 102 minutes 51 seconds