Question

An engineer traveled 150 mi by car and then an additional 630 mi by plane. The rate of the plane was three times the rate of the car. The total trip took 8 h. Find the rate of the car.

Answer 1

Explanation:

150 mile by car x mph

630 mile by plane 3x mph

Total travel time equal 8 hours

150 / x mile / (mile / hour) = hour

630 / 3x mile / (mile / hour) = hour

150/x + 630/3x = 8 hours

450/3x + 630/3x = 8 hours

450 + 630 = 8(3x) = 24x

1080 = 24x

45 = x the rate of the car is 45 mph