document.write( "Question 1091589: Carlos has a box of coins that he uses when playing poker with friends. The box currently contains 39 ​coins, consisting of​ pennies, dimes, and quarters. The number of pennies is equal to the number of​ dimes, and the total value is ​$3.90. How many of each denomination of coin does he​ have?
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Algebra.Com's Answer #706007 by jorel1380(3719)\"\" \"About 
You can put this solution on YOUR website!
Let p be pennies, d be dimes, and q be quarters. The number of pennies is equal to the number of dimes, so p=d. Then:
\n" ); document.write( "p+d+q=39
\n" ); document.write( "2p+q=39 and
\n" ); document.write( "1p+10d+25q=390
\n" ); document.write( "1p+10p+25q=390
\n" ); document.write( "So:
\n" ); document.write( "2p+q=39
\n" ); document.write( "11p+25q=390
\n" ); document.write( "Then solve for p and q. ☺☺☺☺
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