document.write( "Question 623150: Please help me solve this word problem of variation. The volume rate of flow R of blood through an artery varies directly as the fourth power of the radius r of the artery and inversly as the distance d along the artery. If an operation is successful in effectively increasing the radius of an artery by 25% and decreasing its length by 2%, by how much is the volume rate of flow increased? \n" ); document.write( "
Algebra.Com's Answer #391948 by Alan3354(69443)\"\" \"About 
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The volume rate of flow R of blood through an artery varies directly as the fourth power of the radius r of the artery and inversly as the distance d along the artery. If an operation is successful in effectively increasing the radius of an artery by 25% and decreasing its length by 2%, by how much is the volume rate of flow increased?
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\n" ); document.write( "Use F1 for flow, F2 for flow after surgery, r for radius & L for length
\n" ); document.write( "F1 = k*r^4*L
\n" ); document.write( "--> F2 = k*(1.25r)^4/(0.98L)
\n" ); document.write( "F2 =~ k*2.4414/0.98r^4*L
\n" ); document.write( "F2/F1 =~ 2.4912
\n" ); document.write( "Increase = F2/F - 1
\n" ); document.write( "= 1.4912
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\n" ); document.write( "It's 2.49 times the original
\n" ); document.write( "Increased 1.49 times the original, a 149% increase. \n" ); document.write( "
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