Question 217503: cord camera charges $9.00 for processing a 24-exposure roll of film and $12.60 fo processing a 36-exposure roll of film. After Jack's field trip to observe a variety of architectural styles, he tool 17 rolls of film to cord camera and paid $171 for processing. How many ro;;s of each type were processed?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! cord camera charges $9.00 for processing a 24-exposure roll of film and $12.60 fo processing a 36-exposure roll of film. After Jack's field trip to observe a variety of architectural styles, he tool 17 rolls of film to cord camera and paid $171 for processing. How many ro;;s of each type were processed?
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Equations:
Quantity Eq.:: a + b = 17
Value Eq.::::9a + 12.6b = 171
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Multiply thru the Quantity Eq. by 9 to get: 9a + 9b = 9*17
Subtract that from the Value Eq. and solve for "b".
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3.6b = 18
b = 5 (# of rolls of $12.60 film)
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Since a+b=17, a = 12 (# of rolls of $9 film)
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Cheers,
Stan H.
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