SOLUTION: z varies directly as x3 and inversely as y3. If z = 132 when x = 9 and y = 3, find z if x = 10 and y = 9.

Algebra ->  Real-numbers -> SOLUTION: z varies directly as x3 and inversely as y3. If z = 132 when x = 9 and y = 3, find z if x = 10 and y = 9.      Log On


   

Question 1050489: z varies directly as x3 and inversely as y3. If z = 132 when x = 9 and y = 3, find z if x = 10 and y = 9.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
z varies directly as x^3 and inversely as y^3.
z = k*x^3/y^3
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Solve for "k" if z = 132 when x = 9 and y = 3
132 = k*(9^3)/(3^3)
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132 = k*3^3
k = 4.89
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Find z if x = 10 and y = 9.
z = 4.89*10^3/(9^3)
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z = 6.71
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Cheers,
Stan H.