document.write( "Question 471830: A boat goes 240 miles downriver in the same time it can go 160 miles upriver. The speed of the current is 5mph. Find the speed of the boat in still water. \n" ); document.write( "

Algebra.Com's Answer #323557 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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document.write( "Note: D = rt Or t = D/r
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document.write( "A boat goes 240 miles downriver in the same time it can go 160 miles upriver. The speed of the current is 5mph. Find the speed 's' of the boat in still water. 
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document.write( " 240/(s+5mph) = 160/(s-5mph)    Cross Multiplying to solve
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document.write( "  240(s-5) = 160(s+5)
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document.write( "  240s - 5*240 = 160s + 5*160
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document.write( "      80s = 2000
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document.write( "        s = 2000/80
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document.write( "        s = 25mph, the speed of the boat in still water. \r
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document.write( "CHECKING our Answer***
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document.write( "   240/30 = 160/20 = 8 \n" );
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