document.write( "Question 276510: This is a word question. Only using 5 & 10 dollar bills, if you have a total of $90 and 15 total bills how many of each bill do you have? \n" ); document.write( "

Algebra.Com's Answer #201464 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"a\"$ = number of $5 bills
\n" ); document.write( "Let $\"b\"$ = number of $10 bills
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"a+%2B+b+=+15\"$
\n" ); document.write( "(2) $\"5a+%2B+10b+=+90\"$
\n" ); document.write( "--------------
\n" ); document.write( "Multiply both sides of (1) by $\"5\"$
\n" ); document.write( "and subtract from (2)
\n" ); document.write( "(2) $\"5a+%2B+10b+=+90\"$
\n" ); document.write( "(1) $\"-5a+-+5b+=+-75\"$
\n" ); document.write( " $\"5b+=+15\"$
\n" ); document.write( " $\"b+=+3\"$
\n" ); document.write( "and, since
\n" ); document.write( "(1) $\"a+%2B+b+=+15%7D%7D%0D%0A%7B%7B%7Ba+=+15+-+3\"$
\n" ); document.write( " $\"a+=+12\"$
\n" ); document.write( "You have 12 $5 bills and 3 $10 bills \n" ); document.write( "

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