document.write( "Question 530845: Kirsten has 64 coins in her piggy bank.She has $9.25 in dimes and quarters. How many dimes and how many quarters does she have?\r
\n" ); document.write( "\n" ); document.write( "I am doing Singapore math. I am in 5th grade.
\n" ); document.write( "Please help!! \n" ); document.write( "
Algebra.Com's Answer #350213 by oberobic(2304)\"\" \"About 
You can put this solution on YOUR website!
With coin problems, you have to keep track of the number of coins and their values.
\n" ); document.write( "d = number of dimes
\n" ); document.write( "10d = value of the dimes in cents
\n" ); document.write( "q = number of quarters
\n" ); document.write( "25q = value of the quarters in cents
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\n" ); document.write( "10d + 25q = 925 cents (to keep all the amounts in the same units of measure)
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\n" ); document.write( "d + q = 64
\n" ); document.write( "so
\n" ); document.write( "d = 64 - q
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\n" ); document.write( "substitute
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\n" ); document.write( "10(64-q) + 25q = 925
\n" ); document.write( "640 -10q + 25q = 925
\n" ); document.write( "15q = 285
\n" ); document.write( "q = 19
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\n" ); document.write( "d = 64-19 = 45
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\n" ); document.write( "Check the value to be sure this is the answer.
\n" ); document.write( "10d = 10(45) = 450
\n" ); document.write( "25q = 25(19) = 475
\n" ); document.write( "450 + 475 = 925
\n" ); document.write( "Correct.
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\n" ); document.write( "Answer: Kirsten as 19 quarters and 45 dimes.
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\n" ); document.write( "Done.
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