document.write( "Question 431831: if a collection of 27 coins consisting of 20 cent and $2 coins has a value of $23.40 find the number of coins of each domination \n" ); document.write( "

Algebra.Com's Answer #299588 by mananth(16946) $\"\"$ $\"About$

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20 cent coins x Numbers
\n" ); document.write( "$2 coin ------------ y Numbers
\n" ); document.write( "x+y=27 .............1
\n" ); document.write( "x+2y=23.4 .............2
\n" ); document.write( "multiply (1) by -2
\n" ); document.write( "-2x-2y=-54
\n" ); document.write( "0.2x+2y=23.4
\n" ); document.write( "Add the two equations
\n" ); document.write( "-1.8x=-30.6
\n" ); document.write( "/-1.8
\n" ); document.write( "x=17 20 cent coins
\n" ); document.write( "plug value of x in (1)
\n" ); document.write( "x+y=27
\n" ); document.write( "17+y=27
\n" ); document.write( "y=27-17
\n" ); document.write( "y=10 $2 coin
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