A jet and a small plane leave the same airport at the same time and travel in opposite directions at 960 km/h and 560 km/h, respectively. In how many hours will they be 3800 km apart?
A. 2.5 hours
B. 9.5 hours
C. 238.5 km
D. 1400 km

Question

A jet and a small plane leave the same airport at the same time and travel in opposite directions at 960 km/h and 560 km/h, respectively. In how many hours will they be 3800 km apart?
	A.	2.5 hours
	B.	9.5 hours
	C.	238.5 km
	D.	1400 km

espex · Answer

They both start from the same point and the question asks to find the time it takes for them to get 3800km apart. So the total distance is equal to the distance the jet goes plus the distance the plane goes.$$3800 = 960x + 560x \rightarrow 3800 = 1520x \rightarrow \frac{3800}{1520}=x$$ where x is the amount of time traveled. Since C and D are km and the question asks for hours, they are discarded leaving A and B. The math shows us that A is the correct answer and B is unrealistic.