A state school administrator claims that the standard deviation of test scores for 8th grade students who took a life-science assessment test is at most 35. You work for the administrator and you are asked to test this claim. You find that a random sample of size 36 tests that you collected has a standard deviation of 37.6. At α = 0.1, do you have enough evidence to support the administrator’s claim? Assume test scores are normally distributed. Please show all 5 steps involved
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Step 1
Null hypothesis (H0): σ ≤ 35 (The standard deviation of test scores is at most 35.) Alternative hypothesis (H1): σ > 35 (The standard deviation of test scores is greater than 35.) Show more…
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