A manufacturer of compact fluorescent light bulbs advertises that the distribution of the lifespans of these...

A manufacturer of compact fluorescent light bulbs advertises that the distribution of the lifespans of these light bulbs is nearly normal with a mean of 9,000 hours and a standard deviation of 1,000 hours.

(a) What is the probability that a randomly chosen light bulb lasts more than 10,500 hours?
(please round to four decimal places) (b) Describe the distribution of the mean lifespan of 15 light bulbs.

approximately normal with μ = 9000 and σ=1000√15σ=100015
approximately normal with μ = 9000 and σ = 1000
left skewed
right skewed

(c) What is the probability that the mean lifespan of 15 randomly chosen light bulbs is more than 10,500 hours?
(please round to four decimal places)

Expert Solution

Solution: Here concept of normally distributed random variable is used.

Please rate the answer. Thank you.

orchestra answered 2 years ago

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