STATISTICAL SCIENCE and STATISTICAL SCIENCE GE HOMEWORK EXERCISE -

A manufacturing company produces bags of PVC powder. It is known that the variation in weight of bags produced by this process has a normal distribution about its target weight with a standard deviation of 1 kg.

1. What should the manufacturing company set as its target weight in order for 97.5% of its bags to have a weight of at least 100 kg?

2. A random sample of 20 bags was weighed with the following results in kg.

101.26   99.76     98.96     100.36   98.94

98.82     98.51     100.97   101.04   100.31

98.24     100.58   100.20   99.28     99.04

99.95     99.34     99.54     97.89     97.98

Determine a 95% confidence interval for process's actual average bag weight

3. A government inspector wishes to investigate the average weight of bags being produced by this manufacturing company. If a 95% confidence interval for the process's actual average bag weight of width no more than 0.2 kg is required, what is the minimum number of bags that need to be sampled by the government inspector?

Textbook - PROBABILITY and STATISTICAL SCIENCE READER 2015 Associate Professor- Alan J. Branford.