A product manager has conducted a customer

1.) A product manager has conducted a customer satisfaction survey of

30 customers on a scale of 1 to 5. The survey data is shown below. Calculate the mean and standard deviation of the survey and plot a histogram of the data. Does the distribution approximate Normal? Customer Satisfaction rating 1 4 2 3 3 2 4 5 5 5 6 2 7 1 8 4 9 3 10 4 11 4 12 5 13 3 14 3 15 2 16 1 17 5 18 3 19 4 20 3 21 4 22 2 23 4 24 4 25 3 26 3 27 3 28 2 29 2 30 3

2.) A customer relationship manager decided to track customer complaints as part of his ongoing customer satisfaction improvement program. After collecting data for two months, their check sheet appears as follows:

Type of Problem	Frequency (number of times)
Call went to voice mail	8
Items damaged when received	21
Literature not in the box	9
Parts missing	13
Unit not working	2
Delivery was late	3

Construct a Pareto chart including the cumulative % frequency. What is the cumulative percentage of the two leftmost bars?

3.) A quality control engineer monitors the quality of a cylinder production line. He regularly selects a sample of 5 units and measures the diameters. The specification requires the diameter to be 6 inches plus/minus 0.1 inch. The following is a record of the measurements. Is the production process in control? Please use X bar and R charts to make an assessment.

Sample	item 1	item 2	item 3	item 4	item 5
1	6.10	6.15	5.35	5.98	5.95
2	6.35	6.02	6.20	6.10	5.70
3	5.85	5.90	6.20	6.12	6.08
4	6.00	5.80	5.70	6.04	6.17
5	6.15	5.60	6.25	5.99	6.01
6	6.13	6.05	5.89	6.00	5.87
7	5.88	6.03	5.76	6.1 3	6.00
8	6.12	5.45	6.15	6.04	5.91