Two cars are 261 miles apart and travel toward each other on the same road. They meet in 3 hours. One car travels 3 mph faster than the other. What is the average speed of each car?

Let the speed of first car be x mph

the speed of the second one is (x+3) mph

Relative speed=x+x+3 = (2x+3) mph

but

time=distance/speed

thus

3 = (261) / (2x+3)

solving for x we get:

3 (2x+3) = 261

6x+9=261

6x=261-9

6x=252

hence:

x=42 mph

Thus the average speed of first car is 42 mph

Average speed of the second car is (42+3) = 45 mph