2. [40.3 Points] DETAILS BBUNDERSTATlZ 9.2.005.Ml. MY NOTES ASK VOUR TEACHER PRACTICE ANOTHER We use the form 3? = a + bx for the least-squares line. In some computer printouts, the leastsquares equation is not given directlv. Instead, the value of the constant a is given, and the coefcient 5 of the explanatory or predictor variable is displayed. Sometimes a Is referred to as the oonstaht, and sometimes as the lhteroept. Data from a report showed the following relationship between elevation (in thousands of feet} and average number of frost-free davs per vear in a state. A Minitab printout provides the following information. Predictor coo! SE cont '1' P Constant 319.59 28.31 11.21 0.002 Elevation -28.559 3.511 -8.T 0.003 S -11.$03 R-sq - This Notice that "Elevation" is listed under "Predictor." This means that elevation is the explanatory variable x. Its coefficient is the slope b. "Constant" refers to a in the equation 5? = a + bx. {a} use the printout to write the leastsquares equation. 9 = ' + ' ]x (b) For each loco-foot increase in elevation, how many fewer frost-free days are predicted? (Round vour answer to three decimal places.) J (c) The printout gives the value of the coefficient of determination r2. What is the value of r? Be sure to give the correct signfor rhased on the sign of b. {Round your answer to four decimal places.) _l {d} What percentage of the variation in y can be explained by the corresponding variation in x and the leastsquares line? , 1 % IWhat percentage is unexplained? 1% Need Help? - 3. [40.3 Points] BBUNDERSTAT129.2.006. The following Minitab displavr gives information regarding the relationship between the body weight of a child (in kilograms} and the metabolic rate of the child (in ion lccal,r 24 hr). Predictor Coot 55 can: '1' P Constant 0.3354 0.4.143 2.06 0.84 weight 0.3833\"! 0.029\" 13.52 0.000 S - 0.517503 R-Sq - 96.8I {a} Write out the least-squares equation. (I!) For each 1 kilogram increase in weight, how much does the metabolic rate of a child increase? {Use 5 decimal places.) . l {c} What is the value of the correlation coefficient r? {Use 3 decimal places.) J Need Help? W