Solve.
-From a point on a river, two boats are driven in opposite directions, one at 9 miles per hour and the other at 7 miles per hour. In how many hours will they be 80 miles apart?
A)6 hours
B)1 hour
C)7 hours
D)5 hours

Question

Quizplus · Accepted Answer

Since the boats are moving in opposite directions, their speeds add up. So, their combined speed is 9 + 7 = 16 miles per hour. To find the time it takes for them to be 80 miles apart, divide the distance by their combined speed: 80 miles / 16 miles per hour = 5 hours.

Solve. -From a Point on a River, Two Boats Are Driven