Ch 2 project

For this project i picked the car Mercedes Guard S600. First i found out what the mileage was while the speed was 55, 60, 65, 70, 75, and 80. I then graphed the points and since the line was going down the graph was a negative correlation. Then i drew the line of best fit. Then i used two points to find the slope and my slope was -3.9/20. Then i used the point slope form to write my equation y=-3.9/20x+-6.275. I used the graphing calculator to find the correlation coefficient which was r=-.9921. I think the value of r tells the faster you drive the mileage will go down. The equation for best fit is y=-.204x+28.52. I predict that the mileage for a speed of 55 mph is 17 mpg. I also predict that the speed if the mileage is 28 mpg will be about 30mph.