A watch manufacturer creates watch springs whose properties must be consistent. In particular, the standard deviation in their weights must be no greater than 2.0 grams. Fifteen watch springs are selected from the production line and measured; their weights are 8, 9, 4, 6, 9, 6, 3, 1, 10, 3, 7, 10, 7, 5, and 6 grams. Assume squiggley a = 0.10.
a) State the null and alternate hypotheses
b) Calculate the sample standard deviation
c) Determine which test statistic is appropriate (chi-square or F), and calculate its value.
d) Determine the critical value(s).
e) State your decision: Should the null hypothesis be rejected?