Two cars, A and B, 100 miles apart, move toward each other. Car A covers 0.7 mile in the first minute, and then moves with an average speed of 0.8 mile per minute. Car B covers 0.6 mile in the first minute, and then moves with an average speed of 0.7 mile per minute. How many miles apart are the cars after 10 minutes?
a.
85.2
c.
83.7
b.
14.8
d.
16.3

Question

Two cars, A and B, 100 miles apart, move toward each other. Car A covers 0.7 mile in the first minute, and then moves with an average speed of 0.8 mile per minute. Car B covers 0.6 mile in the first minute, and then moves with an average speed of 0.7 mile per minute. How many miles apart are the cars after 10 minutes?
a.
85.2
c.
83.7
b.
14.8
d.
16.3

radar · Answer

Minute 1, they travel 1.3 miles and are 1.3 miles closer or 98.7 miles apart.
You now have to compute how far they travel in the next 9 minutes
you have their avg speed in miles per minute so it is a simple matter to compute distance as you are provided time (9 min) and speed for each car (.8 mpm and .7 mpm).  Subtract that distance from 98.7 and you will have the distance they are apart 10 min after takeoff.  The answer is there.