Question

The table below gives the number of hours spent unsupervised each day as well as the overall grade averages for seven randomly selected middle school students. Using this data, consider the equation of the regression line. 9 = b + b x. for predicting the overall grade average for a middle school student based on the number of hours spent unsupervised each day. Keep in mind, the correlation coefficient may or may not be statistically significant for the data given. Remember, in practice, it would not be appropriate to use the regression line to make a prediction if the correlation coefficient is not statistically significant Hours Unsupervised 0,5 1 3 3.5 4 5 5.5 Overall Grades 96 93 83 82 77 72 68 Table Copy Data Step 5 of 6: Find the estimated value of y when x = 4. Round your answer to three decimal places Prev

Answer 1

Answer:- Given data 0.5 13 315 4 5 515 96 93 83 82 7772 68 Hours unsupervised Overall Grades (X-MA) (Y- My) -3911633 -25.3061 Y- My (X-Mx) X-My 7.3673 14.4286 -2.7143 4.9031 o.ousa -0.3061 X Y 0.5 96 1 93 3 83 3.5 82 G 11 72 68 -212143 -0.2163 0.2851 (1.4286 1.4886 0.6286 -6.5714 r9.5714 -1315714 0.224 -3.5918 -17.0918 -3110206 0.0816 0.6173 311888 9.2245 017857 a. 78 57 2.2851 sp:-116.3571 5.5 Ss 21.6226 571 2215

Mean OF X - 3:2143, Mean of y = 81.5714 Sum of squares (ssx) = 2116286 Sum of products (sp) - -|1643511 Regression Equation = ý = bx + bo SP - 116.36 Bat =-5163 SSX 21.03 a = My-b My = 8):51- (-5143 X 3.21) 99.0a5 -5143X + 99.025 slope = B, - -5143

4 Slope = By : -5.43 -5.43x +११:005) Given x-4 , then -5.43(4) + ११:025 = -21.12+११.०२६ 17.305 Predicted value= 77.305