If it took Boeing $28,718$ hours to produce the eighth 787 jet and the learning-curve factor is $80 \%$, how long did it take to produce the tenth 787 ?

Rick Wing, salesperson for Wave Soldering Systems, Inc. (WSSI), has provided you with a proposal for improving the temperature control on your present machine. The machine uses a hot-air knife to cleanly remove excess solder from printed circuit boards; this is a great concept, but the hot-air temperature control lacks reliability. According to Wing, engineers at WSSI have improved the reliability of the critical temperature controls. The new system still has the four sensitive integrated circuits controlling the temperature, but the new machine has a backup for each. The four integrated circuits have reliabilities of .90, .92, .94, and .96. The four backup circuits all have a reliability of 90 . What is the reliability of the new temperature controller?

Central Electronics Corp. produces semiconductors and has a learning curve of .7. The price per bit is 100 millicents when the volume is $.7 \times 10^{12}$ bits. What is the expected price at $1.4 \times 10^{12}$ bits? What is the expected price at $89.6 \times 10^{12}$ bits?

Barbara Flynn is in charge of maintaining hospital supplies at General Hospital. During the past year, the mean lead time demand for bandage BX-5 was 60 (and was normally distributed). Furthermore, the standard deviation for BX-5 was 7. Ms. Flynn would like to maintain a $90 \%$ service level.

What is the appropriate reorder point?

Rocky Mountain Tire Center sells 20,000 go-cart tires per year. The ordering cost for each order is $\$ 40$, and the holding cost is $20 \%$ of the purchase price of the tires per year. The purchase price is $\$ 20$ per tire if fewer than 500 tires are ordered, $\$ 18$ per tire if 500 or more but fewer than 1,000 -tires are ordered, and $\$ 17$ per tire if 1,000 or more tires are ordered.

What is the total cost of this policy?

Radovilsky Manufacturing Company, in Hayward, California, makes flashing lights for toys. The company operates its production facility 300 days per year. It has orders for about 12,000 flashing lights per year and has the capability of producing 100 per day. Setting up the light production costs $50. The cost of each light is$1. The holding cost is $0.10 per light per year. What is the average holding cost per year?

The monthly sales for Yazici Batteries, Inc., were as follows:

Forecast January sales using each of the following:

i) Naive method.

ii) A 3-month moving average.

iii) A 6-month weighted average using .1, .1, .1, .2, .2, and .3, with the heaviest weights applied to the most recent months.

iv) Exponential smoothing using an $\alpha=.3$ and a September forecast of 18.

v) A trend projection.

Using the data from Problem E.14, how long will it take to complete the 12th plane? The 15th plane? How long will it take to complete planes 12 through 15 inclusive? At $\$ 40$ per hour, what can Alwan, as purchasing agent, expect to pay for planes 12 through $15 ?$

Suad Alwan, the purchasing agent for Dubai Airlines, is interested in determining what he can expect to pay for airplane number 4 if the third plane took 20,000 hours to produce. What would Alwan expect to pay for plane number 5 ? Number 6 ? Use an $85 \%$ learning curve and a $\$ 40$-per-hour labor charge.

The better students at Providence Assessment Center (see Problem E.12) have an $80 \%$ learning curve and can do a task in 20 minutes after just six times. You would like to weed out the weak students sooner and decide to evaluate them after the third unit. How long should the third unit take?

Rocky Mountain Tire Center sells 20,000 go-cart tires per year. The ordering cost for each order is $40, and the holding cost is 20% of the purchase price of the tires per year. The purchase price is$20 per tire if fewer than 500 tires are ordered, $18 per tire if 500 or more-but fewer than 1,000 -tires are ordered, and$17 per tire if 1,000 or more tires are ordered. What is the total cost of this policy?

Rocky Mountain Tire Center sells 20,000 go-cart tires per year. The ordering cost for each order is $40, and the holding cost is 20% of the purchase price of the tires per year. The purchase price is$20 per tire if fewer than 500 tires are ordered, $18 per tire if 500 or more-but fewer than 1,000 -tires are ordered, and$17 per tire if 1,000 or more tires are ordered. How many tires should Rocky Mountain order each time it places an order?

Providence Assessment Center screens and trains employees for a computer assembly firm in Boston. The progress of all trainees is tracked, and those not showing the proper progress are moved to less demanding programs. By the tenth repetition trainees must be able to complete the assembly task in 1 hour or less. Susan Sweaney has just spent 5 hours on the fourth unit and 4 hours completing her eighth unit, while another trainee, Julie Burgmeier, took 4 hours on the third and 3 hours on the sixth unit. Should you encourage either or both of the trainees to continue? Why?

The Mach 10 is a one-person sailboat manufactured by Creative Leisure. The final assembly plant is in Cupertino, California. The assembly area is available for production of the Mach 10 for 200 minutes per day. (The rest of the time it is busy making other products.) The daily demand is 60 boats. Given the information in the table,

Draw the precedence diagram and assign tasks using five workstations.