In the production of molding casing samples are taken at regular and a number of measurements weight made on each casing. The following tables show the weight, kg, of the top margin in ten samples.

Weight	1	2	3	4	5	6	7	8	9	10
(kg)	10	15	9	13	16	16	11	15	16	15

1. Calculate the mean value. (2 marks)
2. Calculate 2 sigma values.(2 marks)
3. Use the estimate made in (a & b) to draw a I or X control chart for ranges with showing the center line (CL), upper and lower control limit (UCL & LCL). Plot the ten measurement unit. (8 marks)
4. Comment on the currentstate of the process in (c). (2 marks)
5. What action, if any more than control limit, what would you recommend on these case? (2 marks)
6. Plot out the 3 sigma normaldistribution chart and comment it. (4 marks)