FOR INSTRUCTOR'S USE

1. a......./6 b....../6 c......./6 d......./6 e....../6 ........../30

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5. a......./6 b....../6 c......./6 d......./6 e....../6 ........../30

1. The data in the following table represent average cholesterol intake in milligram per day and death rate from arteriosclerotic and degenerative heart disease for selected countries of the world.

a. Give the five-number summary for the cholesterol intake.

b. Construct a boxplot for the cholesterol intake and interpret.

d. You want to study the relationship between cholesterol intake and death rate. Define the explanatory variable(x) and response variable(y).

e. You are given that the value of the correlation coefficient between cholesterol intake and death rate is r=0.89.

Interpret 0.89.

What is the proportion of variation in death rate that can be explained by the cholesterol intake?

2. In a certain city the mean price of a quart of milk is 63 cents and the standard deviation is 8 cents. The mean price of a pound of ground beef is $1.75 and the standard deviation is 12 cents. A late-night convenience store charges 89 cents for a quart of milk and $2.12 for a pound of ground beef. Which of these items is relatively more overpriced? Justify your answer.

3. A diastolic blood pressure reading of less than 90 mm is considered normal; a reading of 100 or more is considered dangerous. The distribution of diastolic blood pressure readings of people 30 to 39 years old in the Framingham Heart Study is normally distributed with mean 70 and standard deviation 11.

What proportion of this population has

a. Normal diastolic blood pressure?

b. Dangerous diastolic blood pressure?

c. Diastolic blood pressure between 90 and 100?

4. A large brass company had a labor contract that required any employee layoffs to be based on the employee’s years of service with the company (seniority). A cutoff value is determined, and any employee whose seniority is less than the value is laid off.

At one plant, seniority is normally distributed with mean 15 years and standard deviation 5 years. If 18% are to be laid off, what is the cutoff value?

5. The table below presents the number of violent crimes reported during the past year (y) and the number of schools (x) for 20 cities from different countries around the world.

c. The least squares regression line is y=658-2.5x.

Interpret 658 and -2.5 in the context of the problem.

d. Find the value of the residual for City 6.

e. Interpret the following scatter plot.