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STA2023 – Test 2 Partial List of Topics
Many of these topics will be included on the exam, but not necessarily all of them. Furthermore,
other questions may be asked that are not included in this review. In addition to this review, look
over the labs, worksheets and the assigned problems from the textbook.
NORMAL DISTRIBUTIONS
Do you take a sample of size greater than one?
NO YES
Population Distribution Sampling Distribution
Standard Normal
otherwise proportion of mean of
Curve sample sample
Z X
p
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x
1. Basic Normal Distributions X and Z:
A) Sketch the normal curve, labeling the mean and 1, 2, and 3 standard deviations above and
below the mean.
B) Know what the Empirical Rule is and what it is used for.
C) Find intervals within k standard deviations of the mean and calculate the relative
frequency of data falling within these intervals.
D) Given the value of an observation (x-value), find its z-score.
E) Given a z-score, find the value of the x-value that it corresponds to.
F) Know how to use normalcdf and invnorm on your calculator.
G) Know how to use -1E99 and 1E99 on your calculator and what they represent.
H) Shade the curve and find the proportion of observations are
less than (or greater than) _____.
I) Shade the curve and find the proportion of observations that are between ____
and _____.
J) Understand how to find the probabablity of randomly picking a data (or z-score).
K) Suppose that a z-score was 1.25. Using a complete sentence, explain what this means in
the context of the given problem.
L) Interpret the meaning of the data using the 68-95-99.7 rule.
M) Know the notation (and be able to compute) in these examples: P(1.3 < z < 6.8),
P(z < -.5), P(z > -1.2). Also be able to do the same with x instead of z.
N) Given a percentage under the normal curve, find the value of X associated with it.
O) Remember to include units with story problem answers.
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