speed of boat in still water --- x mph
speed of current ---------- y mph
so speed against the current = x-y mph
and speed with the current = x+y mph
downstream(with the current)
15/(x+y) = 1
x+y = 15
upstream:
15/(x-y) = 5/3
5x - 5y = 45
x - y = 9
add them:
2x = 24
x = 12, then since x+y=15, y = 3
speed of boat is 12 mph, the current is 3 mph
I am having a hard time with this question.
A boat went 15 miles downstream in 1 hour and then returned upstream to its dock in 5/3 hours. if the current of the stream was constant, find the speed of the boat in still water and the speed of the current
1 answer
1 answer