You Must Show All Work for Full Credit!! 1. A sample of 25 light bulbs revealed that the average life span was 855 hours with a standard deviation of 130 hours. Assuming a normal distribution for the lifespan of the population of light bulbs, test the claim at a .01 level of significance that the mean life span of the population of light bulbs is less than 865 hours. (20 pts) a) State the claim (2pt) b) State the Null Hypothesis: (2pt) c) State the Alternative Hypothesis: (2pt) d) Determine the type of test used: (1pt) e) Determine the critical value(s) CV (2pt) f) Find the Test statistic (TS): (8 pt) g) ) Decision and conclusion: (3pts)
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b) The null hypothesis is that the mean life span of the population of light bulbs is equal to or greater than 865 hours. c) The alternative hypothesis is that the mean life span of the population of light bulbs is less than 865 hours. d) This is a one-tailed test Show more…
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