document.write( "Question 314084: 1)Suppose that Q is jointly proportional to R and the Square of S. If Q=24 when R=3 and S=4. Find Q when R=2 and S=3.\r
\n" ); document.write( "\n" ); document.write( "2)When and anvil is dropped into a gorge, the speed with which it strikes the ground is directly proportional to the square root of the distance it falls. An anvil that falls 400 feet hits the ground at a speed of 160 feet per second. Find the height of a cliff over the gorge is a dropped anvil hits the ground ata speed of 128 feet per second.
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Algebra.Com's Answer #224653 by ankor@dixie-net.com(22740)\"\" \"About 
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1)Suppose that Q is jointly proportional to R and the Square of S.
\n" ); document.write( "Q:(R*S^2)
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\n" ); document.write( "If Q=24 when R=3 and S=4. Find Q when R=2 and S=3.
\n" ); document.write( "\"24%2F%283%2A4%5E2%29\" = \"Q%2F%282%2A3%5E2%29\"
\n" ); document.write( "\"24%2F48\" = \"Q%2F18\"
\n" ); document.write( "Q = 9
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\n" ); document.write( "2)When and anvil is dropped into a gorge, the speed with which it strikes the
\n" ); document.write( " ground is directly proportional to the square root of the distance it falls.
\n" ); document.write( "s:\"sqrt%28d%29\"
\n" ); document.write( " An anvil that falls 400 feet hits the ground at a speed of 160 feet per second.
\n" ); document.write( "Find the height of a cliff over the gorge is a dropped anvil hits the ground at a speed of 128 feet per second.
\n" ); document.write( "let h = height of the cliff
\n" ); document.write( "A ratio equation
\n" ); document.write( "\"160%2Fsqrt%28400%29\" = \"128%2Fsqrt%28h%29\"
\n" ); document.write( "same as
\n" ); document.write( "\"160%2F20\" = \"128%2Fsqrt%28h%29\"
\n" ); document.write( "Cross multiply
\n" ); document.write( "\"160sqrt%28h%29\" = 20 * 128
\n" ); document.write( "\"160sqrt%28h%29\" = 2560
\n" ); document.write( "\"sqrt%28h%29\" = \"2560%2F160\"
\n" ); document.write( "\"sqrt%28h%29\" = 16
\n" ); document.write( "Square both sides
\n" ); document.write( "h = 16^2
\n" ); document.write( "h = 256 ft
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