document.write( "Question 360699: IT takes the same amount of time for a boat on the river to go downstream 15 miles as it does to go upstream 9 miles. If the river current is 5mph what is the speed of the bat in still water? \n" ); document.write( "

Algebra.Com's Answer #257405 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "*Note: d = r*t or t = d/r
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document.write( "IT takes the same amount of time ...
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document.write( "Let r represent speed in still water
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document.write( "cross multiply and solve for r 
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document.write( "15(r-5)= 9(r+5)
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document.write( "15r - 75 = 9r + 45
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document.write( "6r = 120
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document.write( "r = 20 mph
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document.write( "checking our answer
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document.write( "15/25 = 9 /15 = 3/5 \n" );
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