Question

Two cars leave towns 340 kilometers apart at the same time and travel toward each other. One car's rate is 14 kilometers per hour more than the other's. If they meet in 2 hours, what is the rate of the slower car?

Answer 1

78 km/h

Explanation:

Let s represent the speed of the slower car. The total speed of the two cars is their closing speed:

(s) + (s+14 km/h) = (340 km)/(2 h)

2s + 14 km/h = 170 km/h . . . . . simplify

s + 7 km/h = 85 km/h . . . . . . . . divide by 2

s = 78 km/h . . . . . . . . . . . . . . . . subtract 7 km/h

The rate of the slower car is 78 km/h.