A light-bulb manufacturer advertises that the average life for its light bulbs is 900 hours. A...

A light-bulb manufacturer advertises that the average life for its light bulbs is 900 hours.

A random sample of 15 of its light bulbs resulted in the following lives in hours.

995 590 510 539 739 917 571 555

916 728 664 693 708 887 849

At the 10% significance level, test the claim that the sample is from a population with a

mean life of 900 hours. Use the P-value method of testing hypotheses. Identify the null and alternative hypotheses,

test statistic, critical value(s) or P-value (or range of P-values) as appropriate, and state the final conclusion that addresses the original claim.

Solutions

Expert Solution

Let denotes the average life for its light bulbs.

orchestra answered 1 year ago

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