document.write( "Question 934453: speed of a boat in still water is 11km/hr. it can go 12 kms uptream and return downstream to the original pointin 2hours45minutes. find speed of stream. \n" ); document.write( "
Algebra.Com's Answer #567442 by mananth(16946)\"\" \"About 
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boat speed = 11 km/h
\n" ); document.write( "current speed = x km/h
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\n" ); document.write( "against current = 11 - x
\n" ); document.write( "with current = 11 + x
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\n" ); document.write( "Total distance = 12 km Total Time= 2.75 hours
\n" ); document.write( "Time upstream + time downstream = 2.75 hours
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\n" ); document.write( "12 /( 11 - x )+ 12 /( 11 + x )= 2.75
\n" ); document.write( "12 ( 11 + x )+ 12 ( 11 - x )= 2.75 ( 121 - 1 X^2 )
\n" ); document.write( "132 + 12 x + 132 -12 x = 332.75 - 2.75 X^2
\n" ); document.write( "264 - -332.75 = -2.75 X^2
\n" ); document.write( "-68.75 = -2.75 X^2
\n" ); document.write( "-2.75 X^2= -68.75
\n" ); document.write( "x2= = 25
\n" ); document.write( "x= +/- 5
\n" ); document.write( "speed of current = 5 km/h \n" ); document.write( "
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