1. The oce manager at a real estate firm makes a pot of co↵eeevery morning. The time before it runs out, y, in hours, depends onthe number of persons x, working in the oce on that day. Supposethat the pairs of (x, y) values from n = 6 days are given in tablebelow. Number of people, x 1 2 3 3 4 5 Time before co↵ee runs out,y 8 4 5 3 3 1 (a) Calculate the standard deviation of responses, s(follow steps on pages 88 and 89). (b) Calculate the 95% confidenceinterval for average number of hours when x⇤ = 4 people are workingin the oce (follow steps on page 90). (c) Interpret your intervalfrom part (b). 94 (d) Calculate and interpret the 95% predictioninterval for the number of hours when x⇤ = 4 people are working inthe oce (follow steps on page 91). (e) Interpret your interval frompart (d). (f) Calculate r2 (follow steps on page 92). (g) Interpretr2. (h) Compute linear correlation coecient r (follow steps on page93). (i) Interpret r.
