It is suspected that a supplier systematically underfills 5 l canisters of detergent.
The filled volumes are assumed to be normally distributed. A small sample of
canisters is measured exactly. This shows that the canisters contain on average
ml. The sample variance
is equal to
confidence interval for the average content of
a canister (in ml).
What is the lower confidence bound?
What is the upper confidence bound?
confidence interval for the average content
in ml is given by: