document.write( "Question 724624: A motorboat takes 3 hrs to make a trip downstream with a 6 mph current. Returning from the trip, on the same current, it took 5 hrs. How do I calculate the speed of the boat that's still in the water?\r
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Algebra.Com's Answer #443811 by stanbon(75887)\"\" \"About 
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A motorboat takes 3 hrs to make a trip downstream with a 6 mph current. Returning from the trip, on the same current, it took 5 hrs. How do I calculate the speed of the boat in still in water?
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\n" ); document.write( "Let speed in still water be \"b\":
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\n" ); document.write( "Downstream DATA:
\n" ); document.write( "time = 3 hrs ; rate = b+6 mph ; distance = r*t = 3(b+6) miles
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\n" ); document.write( "Upstream DATA:
\n" ); document.write( "time = 5 hrs ; rate = b-6 mph ; distance = r*t = 5(b-6) miles
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\n" ); document.write( "Equation:
\n" ); document.write( "distance down = distance up
\n" ); document.write( "3(b+6) = 5(b-6)
\n" ); document.write( "3b + 18 = 5b - 30
\n" ); document.write( "2b = 48
\n" ); document.write( "b = 24 mph (speed of the boat in still water)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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