Complete the following:
1. What is sampling with replacement and why is it used?
2. What proportion of a normal distribution is located between each of the following z-score boundaries?
a. z=-0.50 and z=+0.50
b. z=-0.90 and z=+0.90
c. z=-1.50 and z=+1.50
3. Find the z-score location of a vertical line that separates a normal distribution as described in each of the following.
a. 20% in the tail on the left
b. 40% in the tail on the right
c. 75% in the body on the left
d. 99% in the body on the right
4. For a normal distribution with a mean of µ=80 and a standard deviation of σ=20, find the proportion of the population corresponding to each of the following?
a. scores greater than 85
b. scores less than 100
c. scores between 70 and 90
5. IQ test scores are standardized to produce a normal distribution with a mean of µ=100 & a standard deviation of σ=15. Find the proportion of the population for each of the following IQ categories.
a. Genius or near genius: IQ over 140
b. Very superior intelligence: IQ from `120 to 140
c. Average or normal intelligence: IQ from 90 to 100
6. Information from the Department of Motor Vehicles indicates that the average age of licensed drivers is µ=39.7 years with a standard deviation of σ=12.5 years. Assuming that the distribution of drivers age is approximately normal,
a. What proportion of licensed drivers are more than 50 years old?
b. What proportion of licensed drivers are less than 30 years old?