SOLUTION: If y varies inversely as x and x is increased in the ratio 3:5, how is y changed?

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Question 1047391: If y varies inversely as x and x is increased in the ratio 3:5, how is y changed?
Answer by AnlytcPhil(1807) About Me  (Show Source):
You can put this solution on YOUR website!
If y varies inversely as x...
Then y%22%22=%22%22k%2Fx
and x is increased in the ratio 3:5

Then
how is y changed?
Cross-multiply:

5%28matrix%281%2C2%2COLD%2Cx%29%29%22%22=%22%223%28matrix%281%2C2%2CNew%2Cx%29%29

expr%285%2F3%29%28matrix%281%2C2%2COLD%2Cx%29%29%22%22=%22%22matrix%281%2C2%2CNew%2Cx%29

Replace x by expr%285%2F3%29x in

y%22%22=%22%22k%2Fx

y%22%22=%22%22k%2F%28expr%285%2F3%29x%29%22%22=%22%223k%2F5x%29%22%22=%22%22expr%283%2F5%29%2A%28k%2Fx%29

So y is decreased in the ratio 5:3.

Edwin