Question 1026400
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Hello i need you to help me with this problem, A boat traveled 21 miles upstream on a river in 7 hours. 
The return trip took the boat 3 hours. What is the rate of the current, in miles per hour?
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It is a typical Wind and Current word problem.

See the lesson <A HREF=https://www.algebra.com/algebra/homework/word/travel/More-problems-on-upstream-and-downstream-round-trips.lesson>More problems on upstream and downstream round trips</A> in this site, Problem 1.

This problem is very similar to yours.

In that lesson you will find the detailed solution. 

Consider it as a sample. Read it attentively.

Then solve your problem by substituting your data.

In this way you will learn how to solve similar problems once and for all.
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