document.write( "Question 147774: the current in the river flowed at 3 mph. that boat could travel 24 miles downstrea in 1/2 the time it took to travel 12 miles upstream, what was the speed of the boat in still water? \n" ); document.write( "
Algebra.Com's Answer #108151 by stanbon(75887)\"\" \"About 
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the current in the river flowed at 3 mph. that boat could travel 24 miles downstrea in 1/2 the time it took to travel 12 miles upstream, what was the speed of the boat in still water?
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\n" ); document.write( "Downstream DATA:
\n" ); document.write( "distance = 24 miles ; time = x/2 hrs ; rate = d/t = 48/x mph
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\n" ); document.write( "Upstream DATA:
\n" ); document.write( "distance = 12 miles ; time = x hrs ; rate = d/t = 12/x mph
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\n" ); document.write( "EQUATIONS:
\n" ); document.write( "Let speed of the boat in still water = \"b\":
\n" ); document.write( "b+3 = 48/x
\n" ); document.write( "b-3 = 12/x
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\n" ); document.write( "Subtract 2nd from 1st to get:
\n" ); document.write( "6 = 36/x
\n" ); document.write( "x = 6 hrs
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\n" ); document.write( "Solve for \"b\":
\n" ); document.write( "b+3 = 48/6
\n" ); document.write( "b + 3 = 8
\n" ); document.write( "b = 5 mph (speed of the boat in still water)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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