1.6) The amount of pollutants that are found in waterways near large cities is normally distributed with mean 9 ppm and standard deviation 1.4 ppm. 18 randomly selected large cities are studied. Round all answers to 4 decimal places where possible.

1. What is the distribution of X? X ~ N( _______,_______)
2. What is the distribution of x? x ~ N(_________,________)
3. What is the probability that one randomly selected city's waterway will have more than 9.6 ppm pollutants? ____________
4. For the 18 cities, find the probability that the average amount of pollutants is more than 9.6 ppm. ___________
5. For part d), is the assumption that the distribution is normal necessary? Yes or No
6. Find the IQR for the average of 18 cities. Q1 =_______ ppm Q3 =_______ ppm IQR: _________ ppm

1.7) The amount of coffee that people drink per day is normally distributed with a mean of 14 ounces and a standard deviation of 4.5 ounces. 6 randomly selected people are surveyed. Round all answers to 4 decimal places where possible.

1. What is the distribution of X? X ~ N(_______,_______)
2. What is the distribution of x? x ~ N(_______,______)
3. What is the probability that one randomly selected person drinks between 13.5 and 14.5 ounces of coffee per day___________?
4. For the 6 people, find the probability that the average coffee consumption is between 13.5 and 14.5 ounces of coffee per day. ____________
5. For part d), is the assumption that the distribution is normal necessary? No or Yes
6. Find the IQR for the average of 6 coffee drinkers. Q1 = ________ ounces Q3 = ________ ounces IQR: ________ ounces

1.8) The lengths of adult males' hands are normally distributed with mean 190 mm and standard deviation is 7.3 mm. Suppose that 17 individuals are randomly chosen. Round all answers to 4 where possible.

1. What is the distribution of x? x ~ N(______,_______)
2. For the group of 17, find the probability that the average hand length is less than 188. __________
3. Find the first quartile for the average adult male hand length for this sample size. ______________
4. For part b), is the assumption that the distribution is normal necessary? Yes or No