Q10) Good-Buy Electronics: You own a branch of Good-Buy Electronics and have been told by the manufacturer of Stevuski Televisions that only 5% of their brand of TVs die within one year. Last year, your branch sold 122 such televisions in July. One year later, 13 (about 11%) of them had been returned dead.

(a) Assuming the 5% value quoted by the manufacturer was accurate, what is the mean number of TVs that die within one year in randomly samples of size 122? Round your answer to one decimal place. = (b) What is the standard deviation? Round your answer to one decimal place. = (c) You had 13 TVs die out of 122 (about 11%). With respect to the mean and standard deviation found in parts (a) & (b) respectively, what is the z-score for this many dead TVs? Round your answer to two decimal places. z = (d) Assuming the 5% rate is accurate, would 13 dead TVs in a sample of 122 TVs be considered unusual?

Yes, that is an unusual number of dead TVs.

No, that is not unusual.