a company manufactures light bulb. the company want the bulbs to have a mean life span...

a company manufactures light bulb. the company want the bulbs to have a mean life span of 99t hours. this average is maintained by periodically testing random sample of 25 light bulbs. if the t-value fail between -t0.90 and t0.90, then the company will be satisfied that it is manufacturing acceptable light bulbs. for a random sample, the mean life span of the sample is 1000 hours and the standard deviation is 25 hours. assume the life span are approximately normally distributed. is the company making acceptable light bulb. explain
the company ..... making acceptable light bulbs because the t-value for the sample is t = ....... and t0.90 = ......

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orchestra answered 1 year ago

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