Question 403121
The table lists the cost in millions of dollars for a 30-second super bowl commercial for the selected years. 
table shows years as 1990,1994,1998,2004,2008
table shows cost as 0.8,1.2,1.6,2.3,2.7
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Notice how cost increases 0.4 when years increases by 4
So each each year the cost increases 0.1
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Let 1990 be represented by x = 0 and notice that 
cost is 0.8 when x = 0.

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a)find a linear function f that models the data.
cost(x) = 0.1x + 0.8
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b)estimate the cost in 1987 and compare the estimate to the actual value of $0.6 million. Did your estimate involve interpolation or extrapolation?
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c(-3) =  0.1(-3)+0.8
c(-3) = 0.5
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Note: The model is not perfect as you can see that cost
increases 0.7 in 6 years between 1998 and 2004.
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c)use f to predict the year when the cost could reach $3.2 million. 
Solve 3.2 = 0.1x+0.8
0.1x = 2.4
x = 24
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1990+24 = 2014
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Cheers,
Stan H.
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