Did you ever buy an incandescent light bulb that failed (either burned out or did not work) the first time you turned the switch on? When you put a new light bulb into a light fixture, you expect it to light and most of the time it does. Consider 8-packs of 60-watt bulbs and let x be the number of bulbs in a pack that 'fail' the first time they are used. If 0.02 of all the bulbs of this type fail on their first use and each 8-pack is considered a random sample.
A. List the probability distribution and draw the histogram of x.
B. What is the probability that any one 8-pack has no bulbs that fail on first use?
C. What if the probability that any one 8-pack has no more than one bulb that fails on the first use?
D. Find the mean and standard deviation of x.
E. What is the proportion of the distribution is between m - sigma and m + sigma?
What is the proportion of the distribution is m- 2(sigma) and m + 2(sigma) ?
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