Speed/Time/Distance question

Question

Ms.Clark drove from her home to the museum at an average seed of 40 miles per hour and returned home along the same path at an average speed of 35 miles per hour. If her total driving time for the trip was 2 hours, how many minutes did it take Ms. Clark to drive from her home to the museum?

Answer 1

Distance = Rate x Time

 

             = t x 40  = ( 2- t) * 35

 

 

             40t = 70 - 35t

 

             75t = 70

 

              t = 70/75

 

                  = 14/15

 

            

In hours,

14/15 * 60 min = 56 minutes

 

and

 

2 - 14/15 = 30/15 - 14/15 = 16/15  = 16/15 min = 16/15*60 = 64 min

 

CHECK:

   14/15 * 40 = 560/15 = 37 and 1/3 miles

   16/15 * 35 = 560/15 = 37 and 1/3 miles