<PRE><B>Question 146528</B>
A customer notices that the January bill for picking up 5 bags of trash was $25.60, while the February bill for 7 bags of trash was $27.10. Assume the relationship between the total monthly charges (C) and the number of bags of trash picked up (X) is a linear relationship. Use the data to find the formula that gives (C) in terms of (X) . Then use the formula to predict the cost for picking up 12 bags of trash in one month.
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You have two points relating X and C: (5,25.60) and (7,27.10)
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Slope = (27.10 - 25.60) / (7-5) = 0.75
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Intercept: C = 0.75x + B
25.60 = 0.75*5 + B
B = 21.85
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EQUATION:
C(X) = 0.75X + 21.85
C(12) = 0.75*12 + 21.85
C(12) = $30.85
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Cheers,
Stan H.</PRE>