document.write( "Question 474664: A motorboat travels 268 km in 4 hours going upstream.It travels 420 km going downstream in the same amount of time. What is the rate of the boat in still water and what is the rate of the current? \n" ); document.write( "
Algebra.Com's Answer #325517 by stanbon(75887)\"\" \"About 
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A motorboat travels 268 km in 4 hours going upstream.
\n" ); document.write( "Rate = distance/time = 268/4 = 67 km/hr
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\n" ); document.write( "It travels 420 km going downstream in the same amount of time.
\n" ); document.write( "Rate = distance/time = 420/4 = 104 km/hr\r
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\n" ); document.write( "What is the rate of the boat in still water and what is the rate of the current?
\n" ); document.write( "Equations:
\n" ); document.write( "Upstream: b-c = 67 km/hr
\n" ); document.write( "Downstrm: b+c = 104 km/hr
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\n" ); document.write( "Add and solve for \"b\":
\n" ); document.write( "2b = 171 km/hr
\n" ); document.write( "b = 85.5 km/hr (speed of the boat in still water)
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\n" ); document.write( "Solve for \"c\":
\n" ); document.write( "b+c = 104
\n" ); document.write( "85.5 + c = 104
\n" ); document.write( "c = 18.5 km/hr (speed of the current)\r
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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