document.write( "Question 648794: liviana has $ 2.20 in coins in her change purse. if there is a total of 15 coins how many quarters,dimes,nickles,and pennies does she have? \n" ); document.write( "
Algebra.Com's Answer #406825 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
There are 4 unknowns but only 2 possible
\n" ); document.write( "equations, so this can't be solved directly,
\n" ); document.write( "but it still can be figured out.
\n" ); document.write( "Let \"+p+\" = number of pennies
\n" ); document.write( "Let \"+n+\" = number of nickels
\n" ); document.write( "Let \"+d+\" = number of dimes
\n" ); document.write( "Let \"+q+\" = number of quarters
\n" ); document.write( "The equations are:
\n" ); document.write( "(1) \"+p+%2B+n+%2B+d+%2B+q+=+15+\"
\n" ); document.write( "(2) \"+1%2Ap+%2B+5n+%2B+10d+%2B+25q+=+220+\" ( in cents )
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\n" ); document.write( "The logic steps are:
\n" ); document.write( "(a)
\n" ); document.write( "There doesn't have to be any pennies,
\n" ); document.write( "although there might be, but they will be in
\n" ); document.write( "multiples of 5 or 10
\n" ); document.write( "(b)
\n" ); document.write( "I know there must be less than 9 quarters, since
\n" ); document.write( "9 x 25 = 225, which is too much
\n" ); document.write( "(c)
\n" ); document.write( "I know there must be more than 2 quarters since
\n" ); document.write( "2 x 25 = 50, that leaves 13 coins to make $1.70
\n" ); document.write( "and even if I have 13 dimes, that is only $1.30
\n" ); document.write( "(d)
\n" ); document.write( "Likewise, there must be more that 3 quarters
\n" ); document.write( "3 x 25 = 75 and 220 - 75 = 145, and
\n" ); document.write( "12 x10 = 120 which doesn't make it
\n" ); document.write( "(e)
\n" ); document.write( "Also, there must be more than 4 quarters
\n" ); document.write( "4 x 25 = 100 and 220 - 100 = 120
\n" ); document.write( "There are 11 coins left to make $1.20
\n" ); document.write( "and 11 x 10 = 110, too small
\n" ); document.write( "(f)
\n" ); document.write( "It is possible with 5 quarters since
\n" ); document.write( "5 x 25 = 125 and 220 - 125 = 95
\n" ); document.write( "and 10 x 10 = 100, so it's possible
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\n" ); document.write( "5q = 125 which is 5 coins leaving 10
\n" ); document.write( "220 - 125 = 95
\n" ); document.write( "9d = 90 leaving 1 coin
\n" ); document.write( "1 x 5 = 5
\n" ); document.write( "So, the answer is
\n" ); document.write( "5q
\n" ); document.write( "9d
\n" ); document.write( "1n
\n" ); document.write( "But if I have to use pennies it doesn't work
\n" ); document.write( "--------------------------
\n" ); document.write( "I'll try
\n" ); document.write( "6q
\n" ); document.write( "5d
\n" ); document.write( "4n
\n" ); document.write( "This works, but still no pennies
\n" ); document.write( "---------------------------
\n" ); document.write( "I'll try
\n" ); document.write( "7q
\n" ); document.write( "1d
\n" ); document.write( "This leaves 7 coins to make 35 cents
\n" ); document.write( "and no room for pennies
\n" ); document.write( "---------------------
\n" ); document.write( "8q
\n" ); document.write( "1d
\n" ); document.write( "Leaves 6 coins to make 10 cents
\n" ); document.write( "that's
\n" ); document.write( "1n
\n" ); document.write( "5p
\n" ); document.write( "That's it
\n" ); document.write( "------------
\n" ); document.write( "8 quarters, 1 dime, 1 nickel, and 5 pennies
\n" ); document.write( "are 15 coins that make $2.20\r
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