
Concept explainers
Terminology Consider the graph of a
(i) The graph is bell-shaped, with the highest point over the p.
(ii) The graph is symmetrical about a vertical line through
(iii)The graph crosses the horizontal azis at
(iv)The area under the graph to the right of
(v) The probability that x is between a and b is the area under the curve between a and b.
(i)

The statement “The graph of a normal probability distribution is bell-shaped, with the highest point over the
Answer to Problem 1CR
Solution: The statement “The graph of a normal probability distribution is bell-shaped, with the highest point over the
Explanation of Solution
The graph of a normal probability distribution is bell-shaped, with the highest point over the
(ii)

The statement “The graph of a normal probability distribution is symmetrical about a vertical line through
Answer to Problem 1CR
Solution: The statement “The graph of a normal probability distribution is symmetrical about a vertical line through
Explanation of Solution
The graph of a normal probability distribution is symmetrical about a vertical line through
(iii)

The statement “The graph of a normal probability distribution crosses the horizontal axis at
Answer to Problem 1CR
Solution: The statement “The graph of a normal probability distribution crosses the horizontal axis at
Explanation of Solution
The graph of a normal probability distribution crosses the horizontal axis at
(iv)

The statement “The area under the graph of a normal probability distribution to the right of at
Answer to Problem 1CR
Solution: The statement “The area under the graph of a normal probability distribution to the right of at
Explanation of Solution
The area under the graph of a normal probability distribution to the right of at
(v)

The statement “The probability that x is between a and b is the area under the curve between a and b” is true or false.
Answer to Problem 1CR
Solution: The statement “The probability that x is between a and b is the area under the curve between a and b” is true.
Explanation of Solution
The probability that x is between a andb is the area under the curve between a and b is true. The curve used to describe the distribution of a continuous random variable is called probability distribution curve. It tells what proportion of the population falls within any given interval.
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Chapter 7 Solutions
UNDERSTANDING BASIC STATISTICS (LOOSE)
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