Question

Two trains leave the

station at the same time, one heading west and the other east. The westbound train travels at 80 miles per hour. The eastbound train
travels at 90 miles per hour. How long will It take for the two trains to be 442 miles apart?

Answer 1

Let say time = t

west bound Train travels 80/1hr. For t hours it is (80 x t).
East bound train travels 90/1hr. For t hours it is (90 x t).
Now they are traveling opposite to each other and if they travel exactly for 1 hour it will be 80 + 90. Now for t hours it will be
80t + 90t.
To be 442 miles apart the sum should be equal to 442.
Hence 80t + 90t = 442
170t = 442
t = 442/170
t = 2.6 hours. (0.6 x 60 = 36min)
It takes 2 hours and 36 min for the two trains to be 442 miles apart.