SOLUTION: A boat takes 8 hours to go 6 miles upstream and come back to the starting point. If the speed of the boat is 4 miles per hour in still water, what is the rate of the current? Hint

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Question 839942: A boat takes 8 hours to go 6 miles upstream and come back to the starting point. If the speed of the boat is 4 miles per hour in still water, what is the rate of the current?
Hint: total time taken = time taken to go upstream + time taken to go downstream
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
What is the speed of the water current?
Let c = the speed of the current.


________________speed_____________time___________distance
UP______________4-c_______________(___)__________6
DOWN____________4+c_______________(___)__________6
TOTAL______________________________8

Uniform rates travel, R%2AT=D, R for rate, T for time, D for distance. Use that to find the time expressions.

________________speed_____________time___________distance
UP______________4-c_______________6/(4-c)__________6
DOWN____________4+c_______________6/(4+c)__________6
TOTAL______________________________8

Solve this equation for c:
highlight%286%2F%284-c%29%2B6%2F%284%2Bc%29=8%29