4 b Normal Curve Day 2 Sample vs Pop.notebook May 07, 2014 1

4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
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4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
Remember:
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4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
Sample vs. Population Standard Deviation
If you are asked to find the standard
deviation of a given set of data you use the
population standard deviation
If your data is a sample of a population you
use the sample standard deviation.
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4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
1.) Dan’s scores in Chemistry this semester
were rather inconsistent: 100, 85, 55, 95, 75, 100. For this population, how many scores are
within one standard deviation of the mean? http://firatkim.com/home/img/400px­P_chemistry.png
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4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
2. Professor Halen has 184 students in his college mathematics
lecture class. The scores on the midterm exam are normally
distributed with a mean of 72.3 and a standard deviation of 8.9.
How many students in the class can be expected to receive a score
between 81 and 90? Express answer to the nearest student.
http://api.ning.com/files/5rOKh5yrOt2xkd74obIK7MxM1hk9HoBOEvJgTwIevCQcluB2Taxi9
ASiAcRyTch0rFeU15EZ6mDUy9dykANFBkuXXO6YxsxD/Math.jpg
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4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
3.) Five hundred values are normally distributed with a mean of 125 and a
standard deviation of 10.
a. What percent of the values lies in the interval 115 - 135,
to the nearest percent?
b. What percent of the values is in the interval 100 - 150,
to the nearest percent?
c. What interval about the mean includes 95% of the data?
d. What interval about the mean includes 50% of the data?
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4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
4.) The following are the number of seats available for the given airfare on a flight to Orlando from Buffalo:
What is the mean for this set of data?
http://www.abcteach.com/free/a/airplane1rgb.jpg
Find the population standard deviation to the nearest tenth:
What is the total number of seats that lie within one standard deviation of the mean?
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4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
5.) The weights of ten football players are given below:
200, 195, 235, 205, 265, 240, 210, 250, 180, 250
Find the mean of the weights:
http://www.nd.edu/~afreddos/images/Buffalo_Bills_Logo.gif
Find the population standard deviation for this set of data to the
nearest tenth:
How many weights differ from the mean by more than one standard deviation?
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4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
6.) In a certain school district, the ages of all new teachers hired during the last 5 years are normally distributed. Within this curve, 95.4% of the ages, centered about the mean, are between 24.6 and 37.4 years. Find the mean age and the standard deviation of the data.
http://satnexschool.isti.cnr.it/images/School%20Bus%20­%20Cartoon%207.jpg
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4 b Normal Curve Day 2 Sample vs Pop.notebook
May 07, 2014
Homework p.512 #13, 14
p. 543 #24
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4 b Normal Curve Day 2 Sample vs Pop.notebook
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4 b Normal Curve Day 2 Sample vs Pop.notebook
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4 b Normal Curve Day 2 Sample vs Pop.notebook
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