Two automobiles are 150 kilometers apart and traveling toward each other. One automobile is moving at 60km/h and the other is moving at 40km/h mph. In how many hours will they meet?
A2.5
B1.25
C1.75
D1.5
E2.0
Correct answer
D. 1.5
Explanation
One moves at 60km/h, so in an hour, he’ll travel 60km The other moves at 40km/h, so in an hour, he’ll travel 40km This is towards each other, so, in an hour, we can say that they’ll get 60+40=100km closer. This means that they get closer at 100km/h Given that we have the distance of 150km, and the speed of closure at 100kmh, we can now use the equation S=D/T Rearrange to find T (times both sides by T) S x T = D (now divide both sides by S) T=D/S Time = 150km divided by 100km/h Time = 1.5 hours Or one hour and 30 minutes