SOLUTION: please help me! can someone pls? :( solve the problem. if y varies inversely as x, and y=27 when x=4, find y when x=12

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Question 469620: please help me! can someone pls? :(
solve the problem.
if y varies inversely as x, and y=27 when x=4, find y when x=12

Found 2 solutions by stanbon, Tatiana_Stebko:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
if y varies inversely as x
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y = k/x
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1st: Solve for "k" using "y=27 when x=4"
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27 = k/4
k = 4*27 = 108
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2nd: Equation:
y = 108/x
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3rd: Solve
Find y when x=12
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y = 108/12
y = 9
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Cheers,
Stan H.
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Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
1 way:
y varies inversely as x, so if x increase by 3 (12%2F4=3), then y decrease by 3
y=27%2F3=9
.
.
.
2 way:
if y varies inversely as x, then y=k%2Fx, y=27 when x=4, so 27=k%2F4=>k=27%2A4=108=> y=108%2Fx
when x=12, then y=108%2F12=9