50km/h to friend's house. Coming back home at 56km/h, drives extra 23km and 15 mins extra journey. How long is return journey?

Question

50km/h to friend's house. Coming back home at 56km/h, drives extra 23km and 15 mins extra journey. How long is return journey?

Answer 1

Make the standard r*t=d table.

 

                              rate                       time                distance

going                       50                          x                        50x

back                        56                          x+.25                  56x+14

 

Since the distance is 23 km longer on the return trip, you can set up the equation

50x+23 = 56x + 14

        9   =  6x

        1.5 = x

 

So let's check.

50 k/h * 1.5 h = 75 km

56*1.75 = 98

 

98 is 23 miles longer than 75.

 

So the return journey was an hour and 45 minutes and he went 98 miles. It is not clear if the question wanted how much time ( how long) or how many kilometers(how long), so I give you both.

 

Hope this helped