document.write( "Question 1097343: A coin bank contains coins in dimes and quarters with a total value of $23.70. There are eight fewer dimes than quarters. Find the number of dimes in the bank. \n" ); document.write( "

Algebra.Com's Answer #711743 by ikleyn(52787) $\"\"$ $\"About$

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document.write( "   Q -  D   =    8      (1)    (counting coins)\r\n" );
document.write( "25*Q + 10*D = 2370      (2)    (counting cents)\r\n" );
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document.write( "==========================>  Divide eq(2) by 5; Multiply eq(1) by 2. You will get\r\n" );
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document.write( "  2Q - 2D =  16         (3)\r\n" );
document.write( "  5Q + 2D = 474         (4)\r\n" );
document.write( "------------------------------Add eq(3) and eq(4)\r\n" );
document.write( "  7Q = 490\r\n" );
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document.write( "  ========================>  Q =  = 70.\r\n" );
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document.write( "Answer.  70 quarters and 70-8 = 62 dimes.\r\n" );
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document.write( "Check.   The total is  70*25 + 62*10 = 2370 cents.   ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "2. Light logical analysis\r
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document.write( "Put aside 8 quarters of your collection.\r\n" );
document.write( "Then the updated collection is worth 2370 - 8*25 = 2170 cents.\r\n" );
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document.write( "But this time it consists of equal number of quarters and dimes,\r\n" );
document.write( "and yoU can group quarters and dimes in groups (sets) in a way that each group/set contains exactly one quarter and one dime.\r\n" );
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document.write( "Thus each group is worth 25 + 10 = 35 cents,  and the number od such groups is\r\n" );
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document.write( " = . = 31*2 = 62 groups.\r\n" );
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document.write( "Should I explain further that you have 62 dimes and 62+8 = 70 quarters ??\r\n" );
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document.write( "The same answer. But  MENTAL  solution.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "There is entire bunch of lessons on coin problems\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( "    - 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
\n" ); document.write( "\n" ); document.write( "    - OVERVIEW of lessons on coin word problems\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "You will find there the lessons for all levels - from introductory to advanced,
\n" ); document.write( "and for all methods used - from one equation to two equations and even without equations. \r
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\n" ); document.write( "\n" ); document.write( "Read them and become an expert in solution of coin problems.\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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