# Question

The print on the package of Sylvania CFL 65W replacement bulbs that use only 16W claims that these bulbs have an average life of 8000 hours. Assume that the distribution of lives of all such bulbs is normal with a mean of 8000 hours and a standard deviation of 400 hours. Let x be the life of a randomly selected such light bulb.

a. Find x so that about 22.5% of such light bulbs have lives longer than this value.

b. Find x so that about 63% of such light bulbs have lives shorter than this value.

a. Find x so that about 22.5% of such light bulbs have lives longer than this value.

b. Find x so that about 63% of such light bulbs have lives shorter than this value.

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