The speed of a stream is 6 mph. If a boat travels 52 miles downstream in the same time that it takes to travel 26 miles upstream, what is the speed of the boat in still water?

Answer 1

let the speed of the boat in still water be x mph
using Distance = rate x time or Time = distance/rate
upstream:
time = 26/(x-6)
downstream:
time = 52/(x+6)

26/(x-6) = 52/(x+6)
cross-multiply
52x - 312 = 26x + 156
26x = 468
x = 18

boat's speed is 18 mph