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Problem 11

The following table gives the projected state subsidies (in millions of dollars) to the Massachusetts Bay Transit Authority (MBTA) over a 5-yr period. $$ \begin{array}{lccccc} \hline \text { Year, } \boldsymbol{x} & 1 & 2 & 3 & 4 & 5 \\ \hline \text { Subsidy, } \boldsymbol{y} & 20 & 24 & 26 & 28 & 32 \\ \hline \end{array} $$ a. Find an equation of the least-squares line for these data. b. Use the result of part (a) to estimate the state subsidy to the MBTA for the eighth year \((x=8)\).

Expert verified

The equation of the least-squares line for the given data is \(y = 2.8x + 17.6\). The estimated state subsidy for the MBTA for the eighth year (x = 8) is $40 million.

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