SOLUTION: y is inversely proportional to x. Find the percentage decrease in y when x increases by 150%.

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Question 830693: y is inversely proportional to x. Find the percentage decrease in y when x increases by 150%.
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
y=K%2Fx for some K
Starting from x%5B1%5D=100, we have y%5B1%5D=K%2F100
An increase of 150% of 100 would be an increase of 150 , to a new x value of x%5B2%5D=100%2B150=250 .
With a value of x that is 250%2F100=2.5 times greater,
y will be 2.5 times smaller.
That means that the new value for y will be
y%5B2%5D=y%5B1%5D%2F2.5=y%5B1%5D%2A%281%2F2.5%29=0.4y%5B1%5D .
That is 40% of y%5B1%5D which is a decrease of highlight%28%2260+%25%22%29 from y%5B1%5D .

ANOTHER WAY TO CALCULATE IT:
y%5B2%5D=K%2F250
The decrease, as a fraction of y%5B1%5D , is

Since we want it as a percentage of y%5B1%5D ,
0.6=60%2F100=highlight%28%2260+%25%22%29