Question 1107522
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A boat takes 6 hours to go 30 miles upstream. It can go 72
miles downstream in the same time. Find the rate of the current and the rate of the boat in still water.​ 
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<pre>
                 SPEED           TIME       DISTANCE

UPSTREAM         r-c              6          30

DOWNSTREAM       r+c              6          72
</pre>

{{{system(r-c=30/6,r+c=72/6)}}}


{{{system(r-c=5,r+c=12)}}}


Easily solvable  using Elimination Method.