1. In a large population of adults, the mean IQ is 121 with a standard deviation of 22. Suppose 60 adults are randomly selected for a market research campaign. (Round all answers to 4 decimal places, if needed.)
   • a) The distribution of IQ _____________________ (is approximately normal/is exactly normal/may or may not be normal/is certainly skewed).
   • b) The distribution of the sample mean IQ _____________________ (is approximately normal/exactly normal/not normal/left-skewed/right-skewed) with a mean of _________ and a standard deviation of _________.
   • c) The probability that the sample mean IQ is less than 119 is _________.
   • d) The probability that the sample mean IQ is greater than 119 is _________.
   • e) The probability that the sample mean IQ is between 119 and 125 is _________.
2. The distribution of actual weights of wedges of cheddar cheese produced at a dairy is normal with a mean of 9.9 ounces and a standard deviation of 0.17 ounces. (Round all answers to 4 decimal places, if needed.)
   • a) The probability that a randomly chosen wedge of cheddar cheese is greater than 9.86 is _________.
   • b) If a sample of 18 is randomly chosen, then the distribution of the sample mean weight _____________________ (is approximately normal/not normal/left-skewed/right-skewed) with a mean of and a standard deviation of _________.
   • c) The probability that the sample mean weight of this sample of 18 is less than 9.86 is _________.
   • d) The probability that the sample mean weight of this sample of 18 is greater than 9.86 is _________.
   • e) The probability that the sample mean weight of this sample of 18 is between 9.86 and 9.99 is _________.
   • f) There is only a 4% chance that the average weight of a sample of these 18 cheese wedges will be below _________.
3. At a particular university, students' grades in introductory statistic classes are generally unimodal and skewed to the left with a mean of = 62 and a standard deviation of = 17.8. (Round your answers to four decimal places, if needed.)
   • a) The distribution of students' grades is _____________________ (approximately normal/is exactly normal/may or may not be normal/is left-skewed/is right-skewed).
   • b) If n = 33 students are selected at random, the distribution of the sample mean grade _____________________ (is approximately normal/not normal/left-skewed/right-skewed) with a mean of _________ and a standard deviation of _________.
   • c) The probability that the sample mean grade for these 33 students is less than 63.0 is _________.
   • d) If n = 33 students are selected at random, the distribution of the sample total grade _____________________ (is approximately normal/not normal/left-skewed/right-skewed) with a mean of _________ and a standard deviation of _________.
   • e) The probability that the total grade for these 33 students is less than 2079.0 is _________.
4. Suppose 2% of students drink more than 3 cups of coffee each day. To check this claim, a researcher randomly selected a sample of 147 students and found that 4 drink more than 3 cups of coffee each day. What is the sampling distribution of the sample proportion? (Round your answers to four decimal places, if needed.)
   • The distribution of the sample proportion of students drinking more than 3 cups of coffee each day _____________________ (approximately normal/may not be normal) with a mean of _________ and a standard deviation of _________.
5. Andy is a restaurant owner. He believes 85% of his customers are satisfied with the food quality of his restaurant. From a random sample of 81 customers, what are the following probabilities? (Round your answers to four decimal places, if needed.)
   • a) What is the probability that less than 69 customers are satisfied with the food quality? _________.
   • b) What is the probability that at least 69 customers are satisfied with the food quality? _________.
   • c) What is the probability that the sample proportion of customers who are satisfied with the food quality is between 83% and 90%? _________.