Solve.
-The speed of a stream is 5 mph. If a boat travels 68 miles downstream in the same time that it takes to travel 34 miles upstream, what is the speed of the boat in still water?
A)10 mph
B)18 mph
C)17 mph
D)15 mph

Question

Quizplus · Accepted Answer

Let the speed of the boat in still water be x mph. Downstream speed is (x + 5) mph and upstream speed is (x - 5) mph. The time taken for both journeys is the same, so 68/(x + 5) = 34/(x - 5). Solving this equation gives x = 15 mph.

Solve. -The Speed of a Stream Is 5 Mph. If a a Boat