document.write( "Question 955883: Michael rows downstream on a river. He then returns to the starting point. He traveled a total distance of 16 miles, in 6.25 hours. Michael's average rowing speed in still water is 4 miles/hour. Assume the speed of the river current is constant. What is the speed of the river current? \n" ); document.write( "
Algebra.Com's Answer #583970 by lwsshak3(11628)\"\" \"About 
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Michael rows downstream on a river. He then returns to the starting point. He traveled a total distance of 16 miles, in 6.25 hours. Michael's average rowing speed in still water is 4 miles/hour. Assume the speed of the river current is constant. What is the speed of the river current?
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\n" ); document.write( "let c=speed of river current
\n" ); document.write( "4+c=speed of rowboat downstream
\n" ); document.write( "4-c=speed of rowboat upstream
\n" ); document.write( "travel time = distance /speed
\n" ); document.write( "one-way distance=8 mi
\n" ); document.write( "..
\n" ); document.write( "\"8%2F%284%2Bc%29%2B8%2F%284-c%29=6.25\"
\n" ); document.write( "lcd:(4+c)(4-c)
\n" ); document.write( "8(4-c)+8(4+c)=6.25(4+c)(4-c)
\n" ); document.write( "8(4+c)+8(4-c)=6.25(16-c^2)
\n" ); document.write( "32+8c+32-8c=100-6.25c^2
\n" ); document.write( "6.25c^2=100-64
\n" ); document.write( "6.25c^2=36
\n" ); document.write( "c^2=±√(36/6.25)
\n" ); document.write( "c=±6/2.5=2.4
\n" ); document.write( "speed of river current=2.4 mph \n" ); document.write( "
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