The Lites-Are-Us company advertises that its average light bulbs last 365 days. They want to include a guarantee that a

Question

The Lites-Are-Us company advertises that its average light bulbs last 365 days. They want to include a guarantee that a lightbulb will last between 255 and 475 days. Suppose the distribution of the life expectancy of the light bulbs is normal, with a mean of 365 days and a standard deviation of 55 days. What is the probability of a light bulb lasting between 255 and 475 days?
0.16
0.32
0.75
0.475
0.95

Kunduz · Accepted Answer

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