=+56. Bike sale. The bicycle shop in Exercise 55 estimates using current labor costs that unpacking a bike costs $0.82 on average with a standard deviation of $0.16. Assembly costs $8.00 on average with a standard deviation of $0.88 and tuning costs $4.10 with a standard deviation of $0.90.

Because the costs are directly related to the times, you can use the same assumptions as in exercise 55.

M07_SHAR8696_03_SE_C07.indd 267 14/07/14 7:31 AM 268 CHAPTER 7 The Normal and Other Continuous Distributions