document.write( "Question 1119320: A boy has 180 coins altogether . There are nickels dimes and quarters. Number of dimes is half the number of nickels and quarters. Value of coins is 16. How many of each kind of coin does he have
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Algebra.Com's Answer #734810 by MathTherapy(10552) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( "A boy has 180 coins altogether . There are nickels dimes and quarters. Number of dimes is half the number of nickels and quarters. Value of coins is 16. How many of each kind of coin does he have
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Let number of dimes be D
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document.write( "Then number of nickels and quarters = 2D
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document.write( "We then get: D + 2D = 180
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document.write( "3D = 180
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document.write( "Therefore, number of nickels and quarters = 2(60), or 120
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document.write( "With N & Q being the number of nickels & quarters, we get: N + Q = 120__N = 120 - Q -- eq (i)\r
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document.write( "Since the number of dimes = 60, then value of the dimes = 60(.1) = $6. This means that the value of the nickels and quarters is $10 (16 – 6)
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document.write( "This gives us: .05N + .25Q = 10 ------- eq (ii)
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document.write( ".05(120 – Q) + .25Q = 10 -------- Substituting 120 – Q for N in eq (ii)
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document.write( "6 - .05Q + .25Q = 10
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document.write( ".2Q = 4
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document.write( "You can do your own check! \n" );
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