document.write( "Question 50474: 
My son is in 8th grade and I am trying to help him with\r\n" );
document.write( "math.  Please explain a formula to figure these types\r\n" );
document.write( "of problems.  Thanks\r\n" );
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document.write( "A bike costs $100 more than a scooter. A scooter costs $60\r\n" );
document.write( "more than a skateboard. the total cost of the 3 items is\r\n" );
document.write( "$310. How much is skateboard? Scooter? Bike?
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Algebra.Com's Answer #33531 by AnlytcPhil(1806)\"\" \"About 
You can put this solution on YOUR website!
My son is in 8th grade and I am trying to help him with \r\n" );
document.write( "math.  Please explain a formula to figure these types \r\n" );
document.write( "of problems.  Thanks\r\n" );
document.write( "\r\n" );
document.write( "A bike costs $100 more than a scooter. A scooter costs $60 \r\n" );
document.write( "more than a skateboard. the total cost of the 3 items is \r\n" );
document.write( "$310. How much is skateboard? Scooter? Bike?\r\n" );
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document.write( "Let the cost of a skateboard = n dollars\r\n" );
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document.write( ">>...A scooter costs $60 more than a skateboard...<< \r\n" );
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document.write( "Translation:  the cost of a scooter is n+60 dollars\r\n" );
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document.write( ">>...A bike cost $100 more than a scooter...<<\r\n" );
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document.write( "Translation: the cost of a bike is (n+60) + 100\r\n" );
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document.write( ">>...the total cost of the 3 items is $310...<<\r\n" );
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document.write( "Translation: \r\n" );
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document.write( "skateboard cost + scooter's cost + bike's cost = 310\r\n" );
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document.write( "so\r\n" );
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document.write( "equation  n + n+60 + n+60 + 100 = 310 \r\n" );
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document.write( "Solve for n \r\n" );
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document.write( "             n + n+60 + n+60 + 100 = 310\r\n" );
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document.write( "Collect like terms on left:\r\n" );
document.write( "                          3n + 220 = 310\r\n" );
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document.write( "Subtract 220 from both sides                                   \r\n" );
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document.write( "                                3n = 90\r\n" );
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document.write( "Divide both sides by 3\r\n" );
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document.write( "                                 n = 30\r\n" );
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document.write( "So a skateboard costs $30\r\n" );
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document.write( ">>...A scooter costs $60 more than a skateboard...<< \r\n" );
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document.write( "So a scooter costs $90\r\n" );
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document.write( ">>...A bike cost $100 more than a scooter...<<\r\n" );
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document.write( "So a bike costs $190\r\n" );
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document.write( "Check:\r\n" );
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document.write( ">>...the total cost of the 3 items is $310...<<\r\n" );
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document.write( "$30 + $90 + $190 = $310\r\n" );
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document.write( "So it's correct.\r\n" );
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document.write( "Edwin
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