SOLUTION: If y varies inversely as x and y=40 when x=12,find y when x=15

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Question 1028761: If y varies inversely as x and y=40 when x=12,find y when x=15
Found 2 solutions by stanbon, Natolino1983:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If y varies inversely as x and y=40 when x=12,find y when x=15
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y = k/x
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Solve for "k"::
40 = k/12
k = 480
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Equation::
y = 480/x
If x = 15
y = 480/15 = 32
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Cheers,
Stan H.
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Answer by Natolino1983(23) About Me  (Show Source):
You can put this solution on YOUR website!
If x and y varies inversely, x times y is a constant.
We know that in thin case the constant is x×y= 12×40 = 480. So 15×y must be also 480 then y= 480/15 =32.