Question

A person takes a trip, driving with a constant
speed 89 km/h except for a 16.4 min rest stop.
If the person’s average speed is 75.1 km/h,
how much time is spent on the trip?
Answer in units of h

Answer 1

Let the distance travelled be d and the total time taken be t hours.
Average speed = d/t
Therefore d = 75.1t ...............................(1)
d = 89(t - 16.4/60) ................................(2)
Substituting the value for d in equation (1) into equation (2) gives
75.1t = 89(t - 16.4/60) ..........................(3)
Now you need to solve equation (3) to find the value of t.