Homework Answers
n = 450
sample mean = 13
population sd = 7.4
(a) CI
CI = mean +/- E
E = 0.899
CI = 13 + /- 0.899
CI = 12.101 , 13.899
(b) Assumption for CI to be valid:
Randomization : Each value is sampled independently from each other value.
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