document.write( "Question 1118387: Marissa has
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Algebra.Com's Answer #733678 by ikleyn(52790) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "For a moment, put 5 extra quarters aside.\r\n" );
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document.write( "Then you have a collection of equal number of quarters and dimes, which worth 440 - 5*25 = 440 - 125 = 315 cents.\r\n" );
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document.write( "Since the number of quarters and dimes is the same, you can group the coins in pairs containing one dime and one quarter each.\r\n" );
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document.write( "Each group is worth 25 + 10 = 35 cents, and the number of these groups is   = 9.\r\n" );
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document.write( "So, the original collection has 9 dimes and 9+5 = 14 quarters.\r\n" );
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document.write( "Check.  9*10 + 14*25 = 440 cents.   ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "2. Or you can solve the problem algebraically.\r
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document.write( "Q = D + 5              (1)\r\n" );
document.write( "25*Q + 10*D = 440.     (2)\r\n" );
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document.write( "From eq(1) substitute the expression for Q into equation (2)\r\n" );
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document.write( "25*(D+5) + 10D = 440\r\n" );
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document.write( "25D + 125 + 10D = 440\r\n" );
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document.write( "35Q = 440 - 125 = 315  ====>  Q =  = 9.\r\n" );
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document.write( "And you obtain the same answer.\r\n" );
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document.write( "Notice that this algebraic solution simply follows and repeats the logical solution above.\r\n" );
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document.write( "Simply both methods express the same computational idea.\r\n" );
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\n" ); document.write( "For coin problems and their detailed solutions see the lessons in this site:\r
\n" ); document.write( "\n" ); document.write( "    - Coin problems\r
\n" ); document.write( "\n" ); document.write( "    - More Coin problems\r
\n" ); document.write( "\n" ); document.write( "    - Solving coin problems without using equations\r
\n" ); document.write( "\n" ); document.write( "    - Kevin and Randy Muise have a jar containing coins\r
\n" ); document.write( "\n" ); document.write( "    - Typical coin problems from the archive\r
\n" ); document.write( "\n" ); document.write( "    - Three methods for solving standard (typical) coin word problems\r
\n" ); document.write( "\n" ); document.write( "    - More complicated coin problems\r
\n" ); document.write( "\n" ); document.write( "    - Solving coin problems mentally by grouping without using equations\r
\n" ); document.write( "\n" ); document.write( "    - Santa Claus helps solving coin problem\r
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\n" ); document.write( "\n" ); document.write( "You will find there the lessons for all levels - from introductory to advanced,
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\n" ); document.write( "\n" ); document.write( "Read them attentively and become an expert in this field.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Coin problems\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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