Cholesterol is a fatty substance that is an important part of the outer lining of cells...

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Cholesterol is a fatty substance that is an important part of the outer lining of cells in the body of animals. Its normal range for an adult is 120-240 mg/dl. The Food and Nutrition Institute of the Philippines found that the total cholesterol level for Filipino adults has a mean of 159.2 mg/dl and 84.1% of adults have a cholesterol level below 200 mg/dl. Suppose the total cholesterol level is normally distributed. 8) Determine the standard deviation of this distribution? 9) and 10) What are the quartiles (25% and 75% values) of this distribution? 11) What is the value of the cholesterol level that exceeds 90% of the population? 12) An adult is at moderate risk if cholesterol is more than 1 but less than 2 standard deviations above the mean. What percentage of the population is at moderate risk according to this criterion? 13) An adult is thought to be at high risk if his cholesterol level is more than two standard deviations above the mean. What percentage of the population is at high risk? 14) An adult has low risk if cholesterol level is one standard deviation or more below the mean. What percentage of the population is at low risk? Normal Distribution Functions Norm.dist(x, mean, stdev, c) - calculates the normal distribution for a given value of x, where mean and stdev are the descriptive statistics of the variable in question. Generally, the c argument will always be set to 1, as that calculates the cumulative probability up to the value x. Norm.inv(p, mean, stdev) - calculates the inverse normal distribution. Specifically, given a probability p, it will return the corresponding value of x in the distribution described by mean and stdev. Standard Normal Distribution Functions = x- - Standardize(x, mean, stdev) - returns the standard normal value z for a given value of x with a distribution described by mean and stdev. Recall that z Norm.s.dist(z) - calculates the standard normal distribution for a given value of z. The mean and stdev arguments are not needed, as they are 0 and 1, respectively. Norm.s.inv(p) - calculates the inverse standard normal distribution. Specifically, it returns a value for z, corresponding to a given probability p. Cholesterol is a fatty substance that is an important part of the outer lining of cells in the body of animals. Its normal range for an adult is 120-240 mg/dl. The Food and Nutrition Institute of the Philippines found that the total cholesterol level for Filipino adults has a mean of 159.2 mg/dl and 84.1% of adults have a cholesterol level below 200 mg/dl. Suppose the total cholesterol level is normally distributed. 8) Determine the standard deviation of this distribution? 9) and 10) What are the quartiles (25% and 75% values) of this distribution? 11) What is the value of the cholesterol level that exceeds 90% of the population? 12) An adult is at moderate risk if cholesterol is more than 1 but less than 2 standard deviations above the mean. What percentage of the population is at moderate risk according to this criterion? 13) An adult is thought to be at high risk if his cholesterol level is more than two standard deviations above the mean. What percentage of the population is at high risk? 14) An adult has low risk if cholesterol level is one standard deviation or more below the mean. What percentage of the population is at low risk? Normal Distribution Functions Norm.dist(x, mean, stdev, c) - calculates the normal distribution for a given value of x, where mean and stdev are the descriptive statistics of the variable in question. Generally, the c argument will always be set to 1, as that calculates the cumulative probability up to the value x. Norm.inv(p, mean, stdev) - calculates the inverse normal distribution. Specifically, given a probability p, it will return the corresponding value of x in the distribution described by mean and stdev. Standard Normal Distribution Functions = x- - Standardize(x, mean, stdev) - returns the standard normal value z for a given value of x with a distribution described by mean and stdev. Recall that z Norm.s.dist(z) - calculates the standard normal distribution for a given value of z. The mean and stdev arguments are not needed, as they are 0 and 1, respectively. Norm.s.inv(p) - calculates the inverse standard normal distribution. Specifically, it returns a value for z, corresponding to a given probability p.