trains travling

Question

Two trains leave the station at the same time, one heading east and the other west. The eastbound train travels at a rate of 65 miles per hour. The westbound train travels at a rate of 85 miles per hour. How long will it take for the two trains to be 210 miles apart?

Answer 1

Hi Derrick,

This is a distance, rate, and time problem (d=rt). The variable we are interested in is the time (t) for the trains to be 210 miles apart.

d=distance

r₁=eastbound train rate

r₂=westbound train rate

t=time

For our problem:

d=210

r₁=65

r₂=85

t=t. the value we are looking for.

Thus:

(85+65)t=210

150t=210

t=210/150

t=1.4 hours

t=1 hour, 24 minutes

I hope this helps.