A light bulb manufacturer claims that the average life of their light bulb is more than 1000 hours. To test this claim, a sample of 32 light bulbs had an average life of 1120 hours. Assume the standard deviation is 325 hours. The level of significance is .10. a. State the null and alternative hypothesis. b. State the critical value. c. Calculate the test statistic. d. What is your decision?
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State the null and alternative hypothesis. The null hypothesis (H₀) is that the average life of the light bulbs is equal to 1000 hours. The alternative hypothesis (H₁) is that the average life of the light bulbs is greater than 1000 hours. H₀: μ = 1000 H₁: μ > Show more…
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