1. A trucking company is tracking the total distance and time taken per delivery assignment for each of its 10 trucks. It has recorded the following data:
x = distance (km) y = time (hrs)
545 9.3
212 4.8
450 8.9
410 6.5
225 4.2
395 6.2
530 7.4
295 6.0
510 7.6
450 6.1
You must show your work (formulas with substitutions) to receive full marks.
a) Calculate summary statistics for distance and time: mean, median, range, variance and standard deviation (using the population formulas). (5 marks)
b) Calculate the least-squares line. (2 marks)
c) Interpret the regression results. (2 marks)
d) Estimate the time taken for a delivery distance of 60km. (1 mark)
e) Calculate R^2 and r. (3 marks)