document.write( "Question 791824: A jar has 50 coins: all pennies, nickles, and dimes, with a total value of $3.50. There are twice as many nickles as as pennies. How many are there of each coin?
\n" ); document.write( "p=pennies .01 .01p
\n" ); document.write( "2p=nickles .05 .05(2p)
\n" ); document.write( "d=dimes .10 .10(50-3p)=5-.30p
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\n" ); document.write( "p+2p+d=50
\n" ); document.write( "d=50-3p\r
\n" ); document.write( "\n" ); document.write( ".01p+.05(2p)+5-.3p=3.5
\n" ); document.write( ".01p+.1p+5-.3p=3.5
\n" ); document.write( "-.19p+5=3.5
\n" ); document.write( "5-3.5=.19p
\n" ); document.write( "1.5=.19p
\n" ); document.write( "email is its.me.pinkey3@gmail.com
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Algebra.Com's Answer #479737 by josgarithmetic(39618)\"\" \"About 
You can put this solution on YOUR website!
VARIABLES
\n" ); document.write( "p = count pennies
\n" ); document.write( "n = count nickels
\n" ); document.write( "d = count dimes\r
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\n" ); document.write( "\n" ); document.write( "TRANSLATE THE WORDED DESCRIPTIONS
\n" ); document.write( "\"p%2Bn%2Bd=50\".
\n" ); document.write( "\"0.01p%2B0.05n%2B0.10d=3.50\".
\n" ); document.write( "\"n%2Fp=2%2F1\" (Twice as many nickels as pennies; ratio of nickels to pennies is 2:1).\r
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\n" ); document.write( "\n" ); document.write( "MANAGE EQUATIONS TO MAKE SYSTEM EASIER TO SOLVE
\n" ); document.write( "Clear the fractional nature of the money sum, multiplying both sides by 100, giving \"p%2B5n%2B10d=350\".
\n" ); document.write( "Multiply the ratio equation left&right by p, giving \"n=2p\".\r
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\n" ); document.write( "\n" ); document.write( "ALGEBRAIC SOLUTION STEPS\r
\n" ); document.write( "\n" ); document.write( "The system is now this:
\n" ); document.write( "____________________________________
\n" ); document.write( "\"p%2B5n%2B10d=350\".
\n" ); document.write( "\"p%2Bn%2Bd=50\".
\n" ); document.write( "\"n=2p\".
\n" ); document.write( "____________________________________\r
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\n" ); document.write( "\n" ); document.write( "Solution steps can use the less advanced method of substitution, starting with n. Replace n in the first two equations with n=2p. This gives two equations in two unknowns:
\n" ); document.write( "\"p%2B5%2A2p%2B10d=350\" and \"p%2B2p%2Bd=50\"
\n" ); document.write( "\"11p%2B10d=350\" and \"3p%2Bd=50\"
\n" ); document.write( "Various ways to go, but try solving the count equation for d, and substitute this into the money sum equation:
\n" ); document.write( "\"d=50-3p\", put into... 11p+10*(50-3p)=350
\n" ); document.write( "\"11p%2B500-30p=350\"
\n" ); document.write( "\"-19p=350-500\"
\n" ); document.write( "\"150=19p\"
\n" ); document.write( "\"highlight%28p=7.89%29\" MISTAKE? (No. See \"Second Thought\")\r
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\n" ); document.write( "\n" ); document.write( "(some commentary removed)\r
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\n" ); document.write( "\n" ); document.write( "SECOND THOUGHT: My answer is like your answer. The mistake is not in our work, but in the problem description. \r
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\n" ); document.write( "\n" ); document.write( "CORRECTION TO QUESTION: Amount of money should have been $3.10; with this, problem was solved by original poster.
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