Julie and eric row their boat ( at a constant speed) 40 miles downstream for 4 hours,helped by the current. Rowing at the same rate the trip back against the current takes 10 hours, find the rate of the current
\

Question

Julie and eric row their boat ( at  a constant speed) 40 miles downstream for 4 hours,helped by the current. Rowing at the same rate the trip back against the current takes 10 hours, find the rate of the current
\

kropot72 · Answer

Let x = current rate
On down stream trip rowers rate = 40/4 - x
On th eupstream trip the overall rate 40/10 = (40/4) - x -x
Solving for x gives the rate of the current as 3 mph

anonymous · Answer

this stuff is hard for me, its like a foreign language. Thanks for your help. can you break it down for me though? How did you get 3 I see the equation and still dont get it

anonymous · Answer

sorry

kropot72 · Answer

np. The overall rate on the upstream trip is the rowers rate (given by 40/4 mph) minus the opposing current rate (given as x):$$\frac{40}{10}=(\frac{40}{4}-x)-x$$
This simplifies to:$$4=10-x-x=10-2x$$
Add 2x to both sides and subtract 4 from both sides to get:
$$2x=10-4=6$$
$$x=\frac{6}{2}=3$$

anonymous · Answer

okay thats better , thanks your a life saver!!!

kropot72 · Answer

Gr8. You're welcome :)