document.write( "Question 458515: In a collection of coins consisting of only quarters and nickels, the total value is $1.80 and there are four times as many nickels as quarters. How many nickels are in the collection? \n" ); document.write( "

Algebra.Com's Answer #314545 by josmiceli(19441) $\"\"$ $\"About$

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let $\"+n+\"$ = number of nickels
\n" ); document.write( "Let $\"+q+\"$ = number of quarters
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+n+=+4q+\"$
\n" ); document.write( "(2) $\"+5n+%2B+25q+=+180+\"$ ( in cents )
\n" ); document.write( "----------------
\n" ); document.write( "(1) $\"+q+=+n%2F4+\"$
\n" ); document.write( "Substitute this in (2)
\n" ); document.write( "(2) $\"5n+%2B+25%2A%28n%2F4%29+=+180+\"$
\n" ); document.write( "Multiply both sides by $\"4\"$
\n" ); document.write( "(2) $\"+20n+%2B+25n+=+720+\"$
\n" ); document.write( "(2) $\"+45n+=+720+\"$
\n" ); document.write( "(2) $\"+n+=+16+\"$
\n" ); document.write( "There are 16 nickels
\n" ); document.write( "check:
\n" ); document.write( " $\"+q+=+n%2F4+\"$
\n" ); document.write( " $\"+q+=+4+\"$
\n" ); document.write( "and
\n" ); document.write( "(2) $\"+5n+%2B+25q+=+180+\"$
\n" ); document.write( "(2) $\"+5%2A16+%2B+25%2A4+=+180+\"$
\n" ); document.write( "(2) $\"+80+%2B+100+=+180+\"$
\n" ); document.write( "OK \n" ); document.write( "

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