What is the smallest number of bulbs to be purchased so that

Reference no: EM13559028

A company manufactures a brand of light bulbs with a lifetime in month that is normally distribute with a mean=3 and a variance=1. A consumer buys a number of these bulbs with the intention of replacing them successively as they burn out. The light bulbs have independent lifetimes.

What is the smallest number of bulbs to be purchased so that the succession of light bulbs produce light at least 40 month with probability at least 0.9772?

Reference no: EM13559028

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