Rational functions

Question

The time (t in minutes) that a vehicle can travel varies inversely with the average speed s (in miles per hour) that the vehicle travels. A particular vehicle takes 90 minutes to travel a specific distance at an average speed of 70 mph. determine the time (in minutes) it will take the vehicle to travel the same distance at 60 mph

Answer 1

t = k/s

1.5 = k/70, 90 minutes = 15 hours

k = 105

t = 105/s

t = 105/60 = 1.75 hr = 105 min