Ch13-1
The answers are in row 55 of each sheet (except for solved problems in the book.)
Answers
a) 0.667
b) 2.28%
c) 0.086%
&F
&A
Pioneer Chicken “lite” chicken
east is supposed to contain 400 calories. In reality, the specification limits call for the calories to be 400 ± 50 calories, so the chicken
east is considered acceptable if it contains between 350 and 450 calories.
Suppose the calories content was measured from a sample of chicken
easts. The mean from the sample was 420 calories, and the standard deviation was 15 calories.
a) What is the process capability index, Cpk? Based on this, is this process considered capable?
) According to the given sample data, what percent of the output from the process would be considered unacceptable?
c) Suppose Pioneer Chicken was able to improve the process so that the process mean is now at 400 calories (standard deviation is still 15 calories). Now what percent of the output will be unacceptable?
Ch13-2
No. x1 x2 x3 x4
1 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
2 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
3 XXXXXXXXXX XXXXXXXXXX 29.7046 31.053
4 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
5 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
6 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
7 32.6264 26.3203 XXXXXXXXXX XXXXXXXXXX
8 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
9 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
10 28.2779 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
11 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
12 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
13 XXXXXXXXXX 26.1041 XXXXXXXXXX XXXXXXXXXX
14 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
15 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
16 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
17 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
18 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
19 32.2023 XXXXXXXXXX XXXXXXXXXX 29.3762
20 XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX
Ans:
(a) Control limits for x-bar: XXXXXXXXXXand 35.35, Control limits for R: 0 and 15.29
(c) No, R chart has one point that is higher than the UCL.
You are given measurements for 20 samples. Each sample has 4 measurements.
(a) Find the upper and lower control limits for X-bar chart and R chart.
(b) Create x-bar and r charts.
(c) Is the process in control?
Ch13-3
Sample Number of Defects in Sample
1 11
2 8
3 12
4 9
5 6
6 13
7 18
8 5
9 16
10 4
11 11
12 8
13 12
14 4
15 6
Ans:
LCL XXXXXXXXXX
UCL XXXXXXXXXX
Yes, in control
The data processing department for the Arizona Bank has 5 data entry clerks. Each day their supervisor verifies the accuracy of a random sample of 250 records. A record containing one or more e
ors is considered defective and must be redone. The results of the last 15 samples are shown here.
Compute the control limits, LCL and UCL, for a p-chart using z = 3. Is this process in control?
Ch20-1
Ans:
a)
number of units sold 30
ending inventory 10
units shortage 0
total cost 870
b)
total cost 880
c)
Team 1
In the inventory simulation from class, recall for each month, you had to decide whether to place an order (for hockey sticks) and how many to order. The order quantity was assumed to a
ive in the same month the order is placed. So it would be available to satisfy the demand for that month. No backorders were allowed.
Suppose the selling price is $60/unit, the unit cost is $30, the cost to place an order is $100 per order, cost of shortage is $10 per unit, and holding cost of ending inventory each month is $2 per unit.
In one month, suppose beginning inventory = 15 units, order quantity = 25 units, and demand = 30 units.
a) Determine the following 4 values.
Number of units sold:
Units of ending inventory:
Units short:
Total cost for that month (ordering + holding + shortage):
) If the demand is actually 43 units instead of 30, what is the total cost for that month?
c) Suppose the total order quantity for the year is the same for team 1 and team 2, but team 1 ordered more frequently. Which team will incur the higher total holding cost for the year?
Ch20-2
Ans.
a) $1688
b XXXXXXXXXX -> 118
c) 45.2 -> 46
Inventory
A museum of natural history has opened a gift shop two years ago. One of the top-selling items at the museum’s gift shop is a bird feeder.
The annual demand is 1,460 units, and the supplier charges $50 per unit. The cost of placing an order with the supplier is $60. Annual holding cost per unit is 25% of the unit cost, and the museum operates all 365 days in a year. Under fixed-order quantity policy, management chose to order 200 units each time when the inventory goes down to certain point.
a) With Q of 200 units, what is the total annual relevant cost of the cu
ent policy (ordering + holding cost)?
) Instead of Q of 200, the management could adopt the economic order quantity (EOQ) to lower the inventory related costs. What is the EOQ?
c) Suppose the daily demand has average of 4 units, but it fluctuates according to a normal distribution with standard deviation of 1 unit. The lead time is 10 days. To achieve 95% service level, what is the appropriate reorder point?