Show all work. You may create an excel spreadsheet but it is not necessary for this homework. If your answer is wrong an there is no work you will not get partial credit.

Ulricks Automotive Parts Store stocks a part that has a normal distribution demand pattern during the reorder period. Its average demand during lead time is 800 units, and the standard deviation of demand during lead time is 80 units. What are the safety stock and statistical reorder point that result in a 96 percent service level? Chapter 7 - 10 points (5 points each answer) p. 258-259

Safety Stock =

Statistical Reorder Point =

The daily demand of a product can be specified by a normal distribution. Its average daily demand is 250 units with a standard deviation of 40 units. The delivery lead time of this product is also normally distributed with an average of ten days and a standard deviation of three days. What are the safety stock and reorder point for a 95 percent service level? Chapter 7 10 points pp. 259-262

Safety Stock =

Statistical Reorder Point =

3. LaFlamme Compressors uses a lean production assembly line to make its compressors. In one assembly area, the demand is 300 parts per eight-hour day. It uses a container that holds ten parts. It typically takes about five hours to round-trip a container from one work center to the next and back again. Josh also desires to hold 25 percent safety stock of this part in the system. How many containers should LaFlamme Compressors be using? Chapter 8 8 Points p. 290

No container = DT(1+S)

C

Number of Containers =

4. Using the information from problem 3, if Josh desires to reduce their number of containers to 10, how does this impact the system? What has to change, if it assumed that demand, container size, and safety stock percentage do not change, and what is that change? Chapter 8 p. 290 ( 4 pointes each

What has to change? =

What is that change in units? =

5. Peirong works at Sarahs Wholesale Flower Shoppe, which operates at the 4 sigma level, with about 8,000 DPMO, which was determined recently. At that time, Peirongs process was found to have 1000 total defects. They want to improve to the 5 sigma level, or about 200 DPMO. Assuming nothing else changes, what would their new total defect level have to be? Chapter 8 8 points p. 293-294

Number of Defects =

6. The following sample information was obtained by taking four doughnuts per hour for 12 hours from the Carters Bakerys doughnut process and weighing them: Chapter 8 pp 309-311

Hour	Weights (grams)	Hour	Weights (grams)
1	120, 105, 98, 100	7	110, 102, 101, 99
2	90, 95, 100, 104	8	100, 101, 105, 96
3	100, 102, 100, 110	9	98, 97, 101, 100
4	94, 98, 95, 101	10	99, 100, 97, 110
5	98, 104, 102, 100	11	99, 97, 100, 101
6	104, 97, 108, 100	12	98, 100, 100, 105

For the data shown above,

a. Find the and R for each sample. 24 Points (1 point each answer in table)

Note- An error in computing x or R impacts all other calculations

Hour		R	Hour		R
1			7
2			8
3			9
4			10
5			11
6			12

b. Find the and for the 12 samples. 5 Points (2.5 points each)

Ans.:

=

=

c. Find the 3-sigma UCL and LCL for the mean and range charts. 12 points (3 points each answer)

Ans.: Constants from Table 8.10 page 311-

7. Abels Organic Eggs collects 20 samples with 100 eggs in each sample. They want to construct a P chart to track the proportion of broken eggs in each sample. The table below shows the number of defective eggs per sample. Pp. 312-313

Sample	Eggs	Sample	Eggs	Sample	Eggs
1	6	8	3	15	5
2	8	9	5	16	6
3	9	10	4	17	7
4	3	11	6	18	4
5	4	12	7	19	5
6	1	13	2	20	6
7	3	14	1	TOTAL	95

a. Determine Centerline . 5 Points

Ans.:

b. Determine standard deviation . 5 Points

Ans:

c. Determine the 3-sigma (z = 3.0) UCL and LCL. 10 Points ( 5 point each)