document.write( "Question 990601: A boat can travel 28 mph in still water. If the boat can travel 100 miles with the current in the same time it can travel 80 miles against the current, find the rate of the current r in miles per hour. \n" ); document.write( "
Algebra.Com's Answer #610618 by stanbon(75887)\"\" \"About 
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A boat can travel 28 mph in still water. If the boat can travel 100 miles with the current in the same time it can travel 80 miles against the current, find the rate of the current r in miles per hour.
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\n" ); document.write( "With current DATA:
\n" ); document.write( "dist = 100 miles ; rate = 28+c mph ; time = 100/(28+c)
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\n" ); document.write( "Against current DATA:
\n" ); document.write( "dist = 80 miles ; rate = 28-c mph ; time = 80/(28-c)
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\n" ); document.write( "Equation:
\n" ); document.write( "time = time
\n" ); document.write( "100/(28+c) = 80/(28-c)
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\n" ); document.write( "100(28-c) = 80(28+c)
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\n" ); document.write( "100*28 - 100c = 80*28 + 80c
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\n" ); document.write( "180c = 20*28
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\n" ); document.write( "c = 3.11.. mph (rate of the current)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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