If the total time for the trip was 8 hours, what is the speed on each part of the trip.?

Question

During the first part of a canoe trip, Ken covered 60km at a certain speed. If he then traveled at 24km at a speed that was 4km/h slower . If the total time for the trip was 8 hours, what is the speed on each part of the trip.?

Answer 1

Let v be the speed.

Total travel time = 8

Travel time for first part + Travel time for next part = 8

distance/speed + distance / speed = 8

60 / v + 24 / (v - 4) = 8

60 (v - 4) + 24 v = 8 v ( v - 4)

60 v - 240 + 24 v = 8v^2 - 32 v

8v^2 - 116 v + 240 = 0

4 ( v - 12) (2v - 5 ) = 0

v = 5/12 = 2.5 , v = 12

So speed of the first part = 12 km/h

Spped of the next part = 12 - 4 = 8 km/h