document.write( "Question 498494: sally is 12 years old and her uncle mike is 3 times as old. How many years must pass before her uncle mike is only twice as old as sally? how many years ago was uncle mike 7 times as old. \n" ); document.write( "

Algebra.Com's Answer #337059 by josmiceli(19441) $\"\"$ $\"About$

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$\"+3%2A12+=+36+\"$ is Mike's age now
\n" ); document.write( "Let $\"x\"$ = number of years from now
\n" ); document.write( "when uncle is twice Sally's age
\n" ); document.write( "(a)
\n" ); document.write( " $\"+2%2A%2812+%2B+x%29+=+36+%2B+x+\"$
\n" ); document.write( " $\"+24+%2B+2x+=+36+%2B+x+\"$
\n" ); document.write( " $\"+x+=+36+-24+\"$
\n" ); document.write( " $\"+x+=+12+\"$
\n" ); document.write( "In 12 years Sally will be 24
\n" ); document.write( "In 12 years Uncle will be 48,
\n" ); document.write( "twice Sally's age
\n" ); document.write( "(b)
\n" ); document.write( "Let $\"y\"$ = number of years ago when Uncle was
\n" ); document.write( "7 times as old as Sally
\n" ); document.write( " $\"+7%2A%28+12+-+y+%29+=+36+-+y+\"$
\n" ); document.write( " $\"+84+-+7y+=+36+-+y+\"$
\n" ); document.write( " $\"+6y+=+84+-+36+\"$
\n" ); document.write( " $\"+6y+=+48+\"$
\n" ); document.write( " $\"+y+=+8+\"$
\n" ); document.write( "8 years ago, Uncle was $\"+36+-+8+=+28+\"$
\n" ); document.write( "8 years ago, Sally was $\"+12+-+8+=+4+\"$
\n" ); document.write( "Uncle was 7 times her age \n" ); document.write( "

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