The inspection division of the Measures Department in a public service is interested in estimating the actual amount of soft drink that is placed in 2 -liter bottles at the local bottling plant of a large nationally known soft-drink company. The bottling plant has informed the inspection division that the standard deviation for 2-liter bottles is 0.05 liter.
A random sample of 100 2-liter bottles obtained from this bottling plant indicates a sample average of 2 liters.
a) Set up a 95% confidence interval estimate of the true average amount of soft drink in each bottle.
b) Test the hypothesis that the true average is 2.5 liters against the hypothesis that it is different from 2.5.
Confidence intervals are examined.