A metallurgist has invented a new tungsten alloy for use in the filaments of light bulbs...

A metallurgist has invented a new tungsten alloy for use in the filaments of light bulbs that is supposed to burn brighter with the use of less energy. A company investigates the potential costs of producing the new type of bulb and decides that production would be economically feasible if the bulbs would last an average of longer than 2000 hours in continuous usage. Twenty-five of the new bulbs are tested and found to last an average of 2240 hours with a standard deviation of 600 hours. Is this strong evidence that the average life of all such bulbs is higher than 2000 hours? Translate this into a statistical hypothesis-testing problem and carry out the test. Be sure to give the null and alternative hypotheses, the value of the test statistic, the p-value, and your conclusions.

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orchestra answered 1 year ago

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