# A sales manager for an advertising agency believes

23. A sales manager for an advertising agency believes there is a relationship between the number of contacts and the amount of sales. To verify this belief, the following data were collected: (20 points possible) person # XXXXX $sales 1 14 24 2 12 14 3 20 28 4 16 30 5 46 80 6 23 30 7 48 90 8 50 85 9 55 120 10 50 110 (a) Create a scatter diagram. Put the independent variable on the X (horizontal) axis and put the dependent variable on the Y (Vertical) axis. Be sure to label the axes. (b) Determine the regression equation. State what the y intercept is and what the slope of the linear equation is. Does this appear to be a good model? (c) What is the value of the correlation coefficient, and what is the value of the coefficient of determination? 24. The management of white Industries is considering a new method of assembling its three-wheel golf cart. The present method requires 42.3 minutes on the average to assemble a cart. The new method was introduced, and a time and motion study was conducted on a random sample of 24 carts. The mean assembly time was computed to be 40.6 minutes. The standard deviation of the sample was 2.7 minutes. Using the .10 level of significance, can it be said that the assemble time under the new method is significantly less than before? (20 points possible) a. State the Null and Alternate Hypothesis: H0:__________________________________________________ H1:___________________________________________________ b. Which test statistic will you be using and why? State the cutoff value and the decision rule (when you would reject the null hypothesis). This is the same as stating the rejection area: c. Calculate the test statistic: d. Do you reject or fail to reject the Null Hypothesis? What do you conclude from the analysis?