Two cars are driving in the same direction from the same place. If one travels at 50 mph and the other at 58 mph, how long will it take them to be 40 miles apart?

Question

17489 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-11-13T17:27:55

#5 # hours

Let the required time be #x# hours. The time will be the same for both cars.

The cars will cover different distances because they are travelling at different speeds.

#D = S xx T#

The distance travelled by the slower car = #50xx x# miles.

The distance travelled by the faster car = #58xx x# miles.

The two distances differ by 40 miles.

#58x - 50x= 40#

#8x =40#

#x = 5# hours
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A second method:
The difference in the distances is #40 # miles

The difference in the speeds is #8mph.

The time to make up the 40 miles= #40/8 = 5# hours