SOLUTION: A plane can fly 300 miles in the same time as it takes a car to go 100 miles. If the car travels 100 mph slower than the plane, find the speed of the plane.
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Question 1095352: A plane can fly 300 miles in the same time as it takes a car to go 100 miles. If the car travels 100 mph slower than the plane, find the speed of the plane. Answer by ikleyn(52858) (Show Source):
Let r be the speed of the plane, in mph.
Then the speed of the car is (r-100) mph.
You then have this "time" equation
= ("A plane can fly 300 miles in the same time as it takes a car to go 100 miles").
To solve it, cross-multiply. You will get
300*(r-100) = 100*r ====> 300r - 30000 = 100r ====> 200r = 30000 ====> r = = 150.
Thus the plane speed is 150 miles per hour.
Then the car' speed is 150-100 = 50 mph.
