Ap Statistics Case Study

Question 1
a. Mean age = 960/20=48
b. Standard Deviation = 10.74832
Web address: http://easycalculation.com/statistics/standard-deviation.php
Frequency distribution table for denomination.
Score f(frequency)
1 1
2 2
4 2
5 1
6 3
7 3
8 1
9 3
10 3
12 1 N=30

c. What is the percentage of people who identify themselves as Baptist?

3/20 = .15 x 100 = 15%

What is the mode of church attendance?

5

Question 2

a. What is the Z score for a car with a price of $33,000?

Z=2.85714286

b. What is the Z score for a car with a price of $30,000?

Z=2

Web address for calculator: http://www.danielsoper.com/statcalc3/calc.aspx?id=22

c. At what percentile rank is a car that sold for $30,000?

97.72%
One student’s Math score was 70 and the same individual’s English score was 84. On which exam did the student do better?

Math: +3 points divided by 9.58 SD = .3132
English: + 6 points divided by 12.45 SD = .482

The student did better on the English test.

4.Suppose you administered an anxiety test to a large sample of people and obtained normally distributed scores with a mean of 45 and standard deviation of 4. Do not use web-calculator to answer the following questions. Instead, you need to use the Z distribution table in Appendix A in Jackson’s