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Please Help Really stuck

Please Help Really stuck-example-1
User Qwattash
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1 Answer

4 votes

Answer:

4 2/3 mph

Explanation:

A boat travels 15 miles upstream and 19 miles downstream.

If the boat travels 8 mph in still water, find the speed of the current if the total trip takes 6 hours.

Let c = the speed of the current

then

(8+c) = effective speed downstream

and

(8-c) = effective speed upstream

Write a time equation: time = dist/speed

Upstream time + downstream time = 6 hrs


(15)/(8-c) +(19)/(8+c)=6

120+15c+152-19c=384-6c²

6c²-4c-112=0

c=4 2/3

User Carlosveucv
by
8.0k points