Find the equation of the regression line for the given data
Find the equation of the regression line for the given data. Then construct a scatter plot of the data and draw the regression line. (Each pair of variables has a significant correlation). Then use the regression equation to predict the value of y for each of the given x-values, if meaningful. The caloric and the sodium content (in milligrams) for 6 beef hot dogs are shown in the table below.
Calories, x   Sodium, y
 160                   420
 170                   470
 120                   330
 130   370
 80                     250
 180                   510
(a)x=150 calories
(b)x=100 calories
(c)x=140 calories
(d)x=200 calories
Solution
Scatter plot is as follows:
As this shows a linear trend find slope and intercept.
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a)
| X | Y | XY | XX | 
| 160 | 420 | 67200 | 25600 | 
| 170 | 470 | 79900 | 28900 | 
| 120 | 330 | 39600 | 14400 | 
| 130 | 370 | 48100 | 16900 | 
| 80 | 250 | 20000 | 6400 | 
| 180 | 510 | 91800 | 32400 | 
| 840 | 2350 | 346600 | 124600 | 
| slope | 2.514 | ||
| Intercept | 39.667 | 

