Since 1964, the total number of electors in the electoral college has been 538. In order to declare a winner in a presidential election, a majority, or 270 electoral votes, is needed. The table at right shows the number of electoral votes that the Democratic and Republican parties have received in the presidential elections since 1964.

a. Let x represent the electoral votes for the Democratic Party, and let y represent the votes for the Republican Party. Make a scatter plot of the data.
b. Why are the points nearly linear? What are some factors that make these data not perfectly linear?
c. Sketch the line y = 270 on the scatter plot. How are all the points above the line related?
d. Find the residuals for the line y = 270. What does a negative residual represent?
e. What does a residual value that is close to 0 represent?

Transcribed Image Text:

Electoral Votes Year Democrats Republicans 1964 486 1968191 1972 1976 1980 1984 1988 1992 1996 2000 52 301 520 240 489 525 426 168 159 271 17 297 49 13 370 379 266