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| Question 148153:  Hi, could someone please help me to understand this problem?
 A wood company can convert logs into lumber or plywood. The mill turns out three times as many units of plywood as lumber. A profit of $20 on a untit of lumber and $50 on plywood. How many of each unit must be produced and sold in order to make a profit of $17,680?
 Math is my worst subject and I have a very hard time understanding it.
 Thanks
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! A wood company can convert logs into lumber or plywood. The mill turns out three times as many units of plywood as lumber.
 P and L are the number of units of Plywood and of Lumber.
 Quantity EQUATION: P = 3L
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 A profit of $20 on a unit of lumber and $50 on plywood. How many of each unit must be produced and sold in order to make a profit of $17,680?
 Value EQUATION: 50P + 20L = 17680
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 Rearrange:
 P - 3L = 0
 50P + 20L = 17680
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 Modify to allow elimination:
 50P - 150L = 0
 50P + 20L = 17680
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 Subtract 1st from 2nd so you can solve for "L":
 170L = 17680
 L = 104 (number of units of Lumber)
 Since P = 3L, P = 312 (number of units of Plywood)
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 Cheers,
 Stan H.
 
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