document.write( "Question 1121178: Helen has P2.40 in 25 cents and 5 cents. She has a total of 24 coins. How many 25 cents coins and how many 5 cents coins does she have? \n" ); document.write( "

Algebra.Com's Answer #736934 by ikleyn(52787) $\"\"$ $\"About$

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document.write( "You can start from the system of two equations in two unknowns\r\n" );
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document.write( " x +   y =  24       (1)     (counting coins)\r\n" );
document.write( "5x + 25y = 240       (2)     (counting cents)\r\n" );
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document.write( "Then you can multiply the first equation by 5 (both sides) to get the system in the equivalent form\r\n" );
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document.write( "5x +  5y = 120       (1')\r\n" );
document.write( "5x + 25y = 240       (2')\r\n" );
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document.write( "Now you can subtract equation (1') from equation (2'). In this way, you exclude the unknown x, and you get\r\n" );
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document.write( "a single equation for the unknown y:\r\n" );
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document.write( "25y - 5y = 240 - 120\r\n" );
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document.write( "20y = 120\r\n" );
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document.write( "y =  = 6.\r\n" );
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document.write( "Answer.  6 quarters and  (24-6) = 18 nickels.\r\n" );
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document.write( "Check.   6*25 + 18*5 = 240  cents.   ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.     //   The method I used to solve the system is called the \"Elimination method\".\r
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\n" ); document.write( "\n" ); document.write( "So, on the way, you learned how to solve the system of equations using the Elimination method.\r
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\n" ); document.write( "\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,
\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 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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