Suppose the life span of a light bulb is normally distributed with mean 1000 hours and...

Suppose the life span of a light bulb is normally distributed with mean 1000 hours and standard deviation 75 hours. (a) Find the 57th percentile of this distribution. (b) Find the probability that a random light bulb will last longer than 1100 hours. (c) Find the probability that the life span of a light bulb will be more than 3.14 standard deviations away from the mean. (d) Suppose you take a sample of 15 light bulbs and measure the average life span. Carefully justify whether the Central Limit Theorem applies, and if it does, find the probability that the average life span is between 950 and 1025 hours.

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orchestra answered 11 months ago

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