Chapter 8 Goals
1. Explain why a sample is the only feasible
way to learn about a population
2. Describe methods to select a sample:
Simple Random Sampling
Systematic Random Sampling
Stratified Random Sampling
3. Sampling Error
4. Sampling Distribution Of
_
MA383 Sec I Quiz 3
NAMF.
1 [10] A certain disease is found in onlyLO.05%Jpf people. Find the probability that at least 2
people in a random group of 3000 wouldhave the disease.
a. What is the random variable, in terms of the statement of the problem?
b.
STAT38302 Quiz4 NAME(print):
You will help yourself if you sketch appropriate normal curves and areas.
[S points each partJ A random variable X is normally distributed with u
=
12.45 and a
2
=
0.225.
a. Find P(X < 13.5)
a
b.FindP(X<11.8)
c. Find P(11.8 <
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HW2 Due Wed., Oct. 17 NAME:_
Same rules as before. Circle answers. No ragged edges on paper!
1.[251 Suppose that the Rockwell hardness of a particular alloy is a random variable X with a
normal distribution having parameters = 70 and a = 4.
a. Specificati
Statistics 383
Test 1
Name:
Spring 2010
Section:
Please Print Your Name On Every Page.
Question
Points Score
1
20
2
10
3
10
4
10
5
20
6
15
7
15
Total:
100
If you need extra space use the back of the question sheet.
Please show your work. An unjustied an
Statistics 383
Test 3
Name:
Spring 2010
Section:
Please Print Your Name On Every Page.
Question Points Score
1
10
2
15
3
12
4
10
5
10
6
13
7
15
8
15
Total:
100
If you need extra space use the back of the question sheet.
Please show your work. An unjusti