Question

Two busses leave Billings at the same time. The Seattle bus heads west on I-90 at a speed of 73 miles per hour while the Chicago bus heads east at a speed of 79 miles an hour. How many hours will it take them to be 532 miles apart?

Answer 1

After 3.5 hours buses will be 532 miles apart.

Explanation:

Here one bus is moving west and other is moving east. That is they are moving in opposite direction.

Velocity of Seattle bus = 73 miles per hour west

Velocity of Chicago bus = 79 miles per hour east

Relative velocity = 73 + 79 = 152 miles per hour

We need to find time for which for their separation 532 miles.

Time,

`t=(532)/(152)=3.5hours`

After 3.5 hours buses will be 532 miles apart

Answer 2

3.5 hours

Explanation:

The buses are separating from each other at a speed of 73+79 = 152 miles per hour. Since time = distance/speed, the time it takes to be 532 miles apart is ...

time = (532 miles)/(152 miles/hour) = (532/152) hours = 3.5 hours