document.write( "Question 620130: A canoe takes 7 hours to travel 48 kilometres down a river and back.The rate of the current of the river is 2 kilometres per hour.Find the rate of the canoe in still(calm) water. \n" ); document.write( "

Algebra.Com's Answer #389922 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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document.write( "A canoe takes 7 hours to travel 48 km down a river and back.The rate of the current of the river is 2 kmph.
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document.write( "Find the rateof the canoe in still(calm) water.
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document.write( " D =rt   or  D/r = t
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document.write( "     |Multiplying thru by (r+2)(r-2)so as all denominators = 1
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document.write( "   48(r-2) + 48(r+2) = 7(r+2)(r-2)
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document.write( "         96r = 7(r^2 - 4)
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document.write( "            7r^2 - 96r - 28 = 0  
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document.write( "             (7r+2)(r - 14) = 0  |throwing out negative solution for rate
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document.write( "                       r = 14 kmph is the speed of the canoe in still(calm) water.
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document.write( "CHECKING our Answer***
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document.write( "    = 3hr + 4hr = 7hr
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