Question

Maria can paddle her canoe 2 miles upstream against the current in the same time it would take her to paddle 6 miles downstream. Maria can paddle 2 (mph (miles per hour) in still water. What is the speed of the current?

Answer 1

Let the speed of the current be x mph.

Against the current:
2 = (2-x)t
t = 2/(2-x)

Downstream:
6 = (2+x)t
t = 6/(2+x)

Since the times are equal:
2/(2-x) = 6/(2+x)
2(2+x) = 6(2-x)
4 + 2x = 12 - 6x
8x = 8
x = 1

Therefore, the speed of the current is 1 mph.