document.write( "Question 763518: Suppose that y varies directly with x and inversely with z; y = 27 when x = 21, and z = 7. Write the equation that models the relationship. Then find y when x = 25 and z = 5. \n" ); document.write( "

Algebra.Com's Answer #464896 by Cromlix(4381) $\"\"$ $\"About$

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y varies directly with x and inversely with z
\n" ); document.write( "y = k x/ z
\n" ); document.write( "k = constant of variation
\n" ); document.write( "to find k
\n" ); document.write( "27 = k*21/7
\n" ); document.write( "k = 27 * 7/21
\n" ); document.write( "k = 9
\n" ); document.write( "Equation:
\n" ); document.write( "y = 9*x/z
\n" ); document.write( "y = 9*25/5
\n" ); document.write( "y = 45
\n" ); document.write( "Hope this helps.
\n" ); document.write( ":-) \n" ); document.write( "

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