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Unformatted text preview: se to represent this point
( +1σ or -1σ )?
Question 2: Make a sketch of the distribution and identify this point on the x-axis.
Question 3: Approximately what percent of the data are less than this observation?
(Shade this region on your sketch.)
Question 4: Approximately what percent of the data are greater than this observation?
Answer 1: -1σ . (Negative values for σ represent observations that are less than the
mean. Positive values for σ represent observations that are greater than the mean.)
Answers 2 and 3: Answer 4: approximately 16%
approximately 84% (100% – 16% = 84%) Example 8.4
Suppose scores on an exam are normally distributed with
points are possible on this exam. µ = 80 and σ = 10 . Note: more than 100 Question 1: Students who score a 90 or above get an A. Approximately what percent of
students will get an A?
Question 2: If 300 students take the exam, about how many would fail the exam if failing
is defined as scoring below 60?
Question 3: Suppose the professor decides to...
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This document was uploaded on 02/15/2014 for the course STAT 351 at Oregon State.
- Spring '14
- Normal Distribution