document.write( "Question 1047698: Suppose M is jointly proportional to x and y and inversely proportional to the square of z. If x is doubled, y is decupled, and z is tripled, is the value of M changed, and if so, by what factor?\r
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Algebra.Com's Answer #663236 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
m1 = (x * y) / z^2\r
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\n" ); document.write( "\n" ); document.write( "m2 = (2 * x * 10 * y) / (3 * z^2)\r
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\n" ); document.write( "\n" ); document.write( "m2 / m1 = [(2 * x * 10 * y) / (3 * z^2)] / [(x * y) / (z^2)]\r
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\n" ); document.write( "\n" ); document.write( "since (a/b) / (c/d) is the same as (a/b) * (d/c), your equation becomes:\r
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\n" ); document.write( "\n" ); document.write( "m2 / m1 = (2 * x * 10 * y) / (3 * z^2) * (z^2) / (x * y)\r
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\n" ); document.write( "\n" ); document.write( "this is equivalent to:\r
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\n" ); document.write( "\n" ); document.write( "m2 / m1 = (2 * x * 10 * y * z^2) / (3 * z^2 * x * y)\r
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\n" ); document.write( "\n" ); document.write( "the x and the y and the z^2 in the numerator cancel out the x and the y and the z^2 in the denominator and you are left with:\r
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\n" ); document.write( "\n" ); document.write( "m2 / m1 = (2 * 10) / 3 which is equal to 20/3.\r
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\n" ); document.write( "\n" ); document.write( "multiply both sides of this equation by m1 and you get:\r
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\n" ); document.write( "\n" ); document.write( "m2 = 20 / 3 * m1\r
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\n" ); document.write( "\n" ); document.write( "this says that m2 is 20/3 times as large as m1.\r
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\n" ); document.write( "\n" ); document.write( "to see if this is correct, just provide random values for x, y, and z, and see if the ratio is correct.\r
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\n" ); document.write( "\n" ); document.write( "i used:\r
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\n" ); document.write( "\n" ); document.write( "x = 5
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\n" ); document.write( "\n" ); document.write( "m1 = x * y / z^2 becomes m1 = (5 * 10) / (225) which becomes m1 = 50 / 225\r
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\n" ); document.write( "\n" ); document.write( "m2 = (2 * x * 10 * y) / (3 * z^2) becomes m2 = (2 * 5 * 10 * 10) / (3 * 225) which becomes m2 = 1000 / 675.\r
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\n" ); document.write( "\n" ); document.write( "if you take 50 / 225 and multiply it by 20 / 3, you get 1000 / 675.\r
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\n" ); document.write( "\n" ); document.write( "this confirmed, for me, that the solution is good and that m2 is 20/3 times as large as m1.\r
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\n" ); document.write( "\n" ); document.write( "i believe this is what you're looking for.\r
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