Session III Quiz

1548 Words Mar 29th, 2015 7 Pages
Concordia University/Green Bay Site

Session III Quiz
By
Brad Skenandore

Professor Francois
AL 169 Statistical Methods
20 January 2014

Honor Pledge
As I develop in mind, body, and spirit, I pledge on my honor that I have not given, received, witnessed, nor have knowledge of unauthorized aid on this or [assignment, quiz, paper, test]. 2
Pg 212 #14) A normal population has a mean of 12.2 and a standard deviation of 2.5.
A) Compute the z value associated with 14.3.
- z = (14.3 – 12.2)/2.5 z value is .84

B) What proportion of the population is between 12.2 and 14.3?
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A) What is the standard error of the mean in this example?

- 80/square root of 40 = 12.65

B) What is the likelihood the sample mean is greater than 320 minutes?

- (320 – 330)/80/(sr of 40) = -10/12.65 = -.79. -.79 on the curve is .2852. Using the equation .5000 - .2852 gives the probability of .2148 or approximately 21% likelihood that it will be greater than 320 minutes.

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C) What is the likelihood the sample mean is between 320 and 350 minutes?

- We must first find what the sample would be for the curve if it is greater than 350 minutes. We would find this by (350 – 330)/80(sr of 40) = 20/12.65 = 1.58. 1.58 on the curve is .4429. We then use the equation .4429 - .2852 (.2852 found in part B) to find likelihood of it falling between 320 and 350 minutes being .1577 or approximately 16%

D) What is the likelihood the sample mean is greater than 350 minutes?

- Using what we found in part C we can do .5000 - .4429 = .0571 or approximately 6% likelihood that it will be greater than 350 minutes.

Pg 254 #48) Refer to the Real Estate data, which report information on the homes sold in the Denver, Colorado, area last year.

A) Compute the mean and the standard deviation of the distribution of the selling prices for the homes. Assume
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