Answer:3.25 mph and 1.25 mph
Explanation:
Let s - speed in still water, c - speed of current.
We have the following equations:
2(s + c) = 9
2(s - c) = 4
Simplify:
s + c = 4.5
s - c = 2
Add up and solve for s:
2s = 4.5 + 2
2s = 6.5
s = 6.5/2
s = 3.25 mph
Find c:
c = 3.25 - 2 = 1.25 mph