document.write( "Question 646190: Suppose that Maria has 150 coins consisting of pennies, nickels, and dimes. The number of nickels she has is 9 less than twice the number of pennies; the number of dimes she has is 21 less than three times the number of pennies. How many coins of each kind does she have? \n" ); document.write( "
Algebra.Com's Answer #405762 by stanbon(75887)\"\" \"About 
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Suppose that Maria has 150 coins consisting of pennies, nickels, and dimes. The number of nickels she has is 9 less than twice the number of pennies; the number of dimes she has is 21 less than three times the number of pennies. How many coins of each kind does she have?
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\n" ); document.write( "Equations:
\n" ); document.write( "p + n + d = 150
\n" ); document.write( "n = 2p - 9
\n" ); document.write( "d = 3p - 21
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\n" ); document.write( "Substitute for \"n\" and for \"d\" and solve for \"p\":
\n" ); document.write( "p + 2p-9 + 3p-21 = 150
\n" ); document.write( "6p = 180
\n" ); document.write( "p = 30 (# of pennies)
\n" ); document.write( "n = 2p-9 = 51 (# of nickels)
\n" ); document.write( "d = 3p-21 = 69 (# of dimes)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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