document.write( "Question 666381: April has 100 stamps - some of which are worth 20 cents each and the rest are worth 17 cents each. If the total value of the stamps is $18.83, how many 17 cnets stamps does april have?\r
\n" ); document.write( "\n" ); document.write( "I have tried .2(50y)+.17y = 18.83 so far \n" ); document.write( "

Algebra.Com's Answer #414435 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+a+\"$ = number of 20 cent stamps
\n" ); document.write( "Let $\"+b+\"$ = number of 17 cent stamps
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+a+%2B+b+=+100+\"$
\n" ); document.write( "(2) $\"+.2a+%2B+.17b+=+18.83+\"$
\n" ); document.write( "-----------------------
\n" ); document.write( "(2) $\"+20a+%2B+17b+=+1883+\"$
\n" ); document.write( "Multiply both sides of (1) by $\"+17+\"$
\n" ); document.write( "and subtract (1) from (2)
\n" ); document.write( "(2) $\"+20a+%2B+17b+=+1883+\"$
\n" ); document.write( "(1) $\"+-17a+-+17b+=+-1700+\"$
\n" ); document.write( " $\"+3a+=+183+\"$
\n" ); document.write( " $\"+a+=+61+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+61+%2B+b+=+100+\"$
\n" ); document.write( "(1) $\"+b+=+100+-+61+\"$
\n" ); document.write( "(1) $\"+b+=+39+\"$
\n" ); document.write( "61 = number of 20 cent stamps
\n" ); document.write( "39 = number of 17 cent stamps
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+.2%2A61+%2B+.17%2A39+=+18.83+\"$
\n" ); document.write( "(2) $\"+12.2+%2B+6.63+=+18.83+\"$
\n" ); document.write( "(2) $\"+18.83+=+18.83+\"$
\n" ); document.write( "OK
\n" ); document.write( " \n" ); document.write( "

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