document.write( "Question 830693: y is inversely proportional to x. Find the percentage decrease in y when x increases by 150%. \n" ); document.write( "

Algebra.Com's Answer #500932 by KMST(5328) $\"\"$ $\"About$

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$\"y=K%2Fx\"$ for some $\"K\"$
\n" ); document.write( "Starting from $\"x%5B1%5D=100\"$ , we have $\"y%5B1%5D=K%2F100\"$
\n" ); document.write( "An increase of 150% of $\"100\"$ would be an increase of $\"150\"$ , to a new $\"x\"$ value of $\"x%5B2%5D=100%2B150=250\"$ .
\n" ); document.write( "With a value of $\"x\"$ that is $\"250%2F100=2.5\"$ times greater,
\n" ); document.write( " $\"y\"$ will be $\"2.5\"$ times smaller.
\n" ); document.write( "That means that the new value for $\"y\"$ will be
\n" ); document.write( " $\"y%5B2%5D=y%5B1%5D%2F2.5=y%5B1%5D%2A%281%2F2.5%29=0.4y%5B1%5D\"$ .
\n" ); document.write( "That is 40% of $\"y%5B1%5D\"$ which is a decrease of $\"highlight%28%2260+%25%22%29\"$ from $\"y%5B1%5D\"$ .
\n" ); document.write( "
\n" ); document.write( "ANOTHER WAY TO CALCULATE IT:
\n" ); document.write( " $\"y%5B2%5D=K%2F250\"$
\n" ); document.write( "The decrease, as a fraction of $\"y%5B1%5D\"$ , is
\n" ); document.write( "

\n" ); document.write( "Since we want it as a percentage of $\"y%5B1%5D\"$ ,
\n" ); document.write( " $\"0.6=60%2F100=highlight%28%2260+%25%22%29\"$ \n" ); document.write( "

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