Math Problem

Question

When Fritz drives to work his trip takes 40 minutes, but when he takes the train it takes 30 minutes. Find the distance Fritz travels to work if the train travels an average of 15 miles per hour faster than driving. Assume that the train travels the same distance as the car.

Answer 1

 

 40 min = 2/3 hour

 30 min = 1/2 hour

 

 2/3 hour * r = 1/2 * (r+ 15)

 

 2/3 * r = 1/2*r + 15/2

 

 4r = 3r + 45

 

r = 45

 

2/3 * 45 = 30 miles

 

 

car:  45 mph for 30 miles takes 30/45 = 2/3 hour = 40 min

train: 60 mph for 30 miles takes 30/60 = 1/2 hour = 30 min

 

30 miles