Question

A mill operator is concerned that bags are not being filled to the stated 1000g of grain. 20 bags are randomly weighed and results recorded. There is a sign on the machine that states "grain volumes dispensed follow a normal distribution". a) If a one sample t-test is used, write down the decision rule in terms of a test statistic and calculate the value of the test statistic manually. Use 5% level of significance. b) State the two assumptions of this test and their likely validity.

Bag Weight
1,968.22
2,918.98
3,942.76
4,1024.02
5,988.96
6,1057.26
7,987.28
8,970.06
9,947.76
10,1003.18
11,1005.7
12,1076.16
13,931.36
14,990.06
15,950.64
16,1058.82
17,1036.26
18,928.64
19,898.16
20,978.54

Answer 1