Reference no: EM132805446
Question: Bill Kime's bowling ball factory makes bowling balls of adult size and weight only. The standard deviation in the weight of a bowling ball produced at the factory is known to be 0.12 pounds. Each day for 24 days, the average weight, in pounds, of nine of the bowling balls produced that day has been assessed as follows.
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DAY AVERAGE (LB)
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DAY AVERAGE (LB)
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1 16.3
2 15.9
3 15.8
4 15.5
5 16.3
6 16.2
7 16.0
8 16.1
9 15.9
10 16.2
11 15.9
12 15.9
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13 16.3
14 15.9
15 16.3
16 16.2
17 16.1
18 15.9
19 16.2
20 15.9
21 15.9
22 16.0
23 15.5
24 15.8
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a) Establish a control chart for monitoring the average weights of the bowling balls in which the upper and lower control limits are each two standard deviations from the mean. What are the values of the control limits?
b) If three standard deviations are used in the chart, how do these values change? Why?
c) Plot the monthly sales data
The monthly sales for Telco Batteries Inc. were as follows:
MONTH SALES
JANUARY 20
FEBRUARY 21
MARCH 15
APRIL 14
MAY 13
JUNE 16
JULY 17
AUGUST 18
SEPTEMBER 20
OCTOBER 20
NOVEMBER 21
DECEMBER 23
1) Plot the monthly sales data
2) Forecast January sales using each of the following;
1. naïve method
2. A 3-month moving average
3. A 6-months weighted average using .1,.1,.2,.2, and .3, with the heaviest weights applied to the most recent months.
4. Exponential smoothing using an a = .3 and a September forecast of 18.
5. A trend projection.