Question 833401
During a football game, the parents of the football players sell pretzels and popcorn to raise money for new uniforms. 
They charge $2.50 for a bag of popcorn and $2 for a pretzel. 
The parents collect $336 in sales during the game. 
They sell twice as many bags of popcorn as pretzels. 
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How many bags of popcorn do they sell? How many pretzels do they sell?" 
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Quantity Eq:: pop = 2*pret
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Value Eq::: 2.5pop + 2pret = 336 dollars
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Substitute for "pop" and solve for "pret"::
2.5(2*pret) + 2*pret = 336 dollars
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5pret + 2pret = 336
7pret = 336
# of pretzels = 336/7 = 48 
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# of popcorn = 2*# of pretzels = 96
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Cheers,
Stan H.
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