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# Comparing z-scores and probability

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1. An article in USA Today stated that "Internal surveys paid for by directory assistance providers show that even the most accurate companies give out wrong numbers 15% of the time." Assume that you are testing such a provider by making 10 requests and also assume that the provider gives the wrong telephone number 15% of the time. Find the probability of getting at most, one wrong number. (Assume the Binomial distribution applies.)

0.347
0.544
0.653
0.456

2. Comparing Scores. Three students take equivalent tests of a sense of humor and, after the laughter dies down, their scores are calculated. Which is the lowest relative score?
1. A score of 144 on a test with a mean of 128 and a standard deviation of 34?
2. A score of 90 on a test with a mean of 86 and a standard deviation of 18?
3. A score of 18 on a test with a mean of 15 and a standard deviation of 5?

Cannot determine from the information provided.

3. Comparing a z Score. Heights of women have a mean of 63.6 inches and a standard deviation of 2.5 inches. Julia Roberts, who is one of the most successful actresses in recent years, has a height that converts to a z score of 2.16. How tall (in inches) is Julie Roberts?

69 inches.
59 inches.
Can not convert z scores to inches, impossible to answer the question.
A sample size is not given; accordingly the standard error of the mean can not be calculated; impossible to answer the question.