ECON 230
TEST 2 REVIEW SHEET
Readings the test will cover:
Chapter 5: Sections 5.1-5.4, 5.8
Chapter 6: Sections 6.1-6.6
Chapter 7:
Chapter 8: Sections 8.1-8.4
Important terms and phrases:
Chapters 5 and 6:
- Discrete random variable
- Discrete probability
distribution
- Poisson probability
distribution
- Continuous random
variable
- Continuous probability
distribution
- Normal distribution
- Standard normal
distribution
- Area under the normal
curve
- Finding z- and x-values
- Using probability tables
- Sampling distribution of a
sample mean
- Mean and standard
deviation of a sample mean
Chapter 7:
- Population distribution
- Sampling distribution
- Sampling error
- Mean and standard
deviation of
x
- Shape of the sampling
distribution of
x
- Central limit theorem
- Population proportion
- Sample proportion
Chapter 8:
- Point estimate
- Margin of error
- Confidence interval
- Confidence and
significance levels
- Estimating confidence
intervals when
is known
- Estimating confidence
intervals when
is not
known
- t – distribution
1. A publisher introduces a new weekly magazine for teenagers. The company’s marketers estimate
that the sales x (in thousands) will be approximated by the following distribution.
a) Check whether the given distribution is a probability distribution.
b) If it is a probability distribution, find the mean for this distritbution.
c) If it is a probability distribution, find the standard deviation.
2. Problem 5.94. Replace part b) with the following question:
b) What is the probability that Borok’s Electronics Company receives at least two applications in
xP(x)
10 .200
15 .300
20 .150
25 .350
1
