Concept explainers
(a)
To Calculate: the
(a)

Answer to Problem R7.6RE
0.3707
Explanation of Solution
Given:
Formula used:
Calculation:
The z-score is
The associatively probability using table
(b)
To find: the
(b)

Answer to Problem R7.6RE
Mean = 100
Standard deviation = 1.9365
Explanation of Solution
Given:
Formula used:
Calculation:
The mean of the sampling distribution of the sample mean
(c)
To Calculate: the probability that the average WAIS score of an SRS of 60 people is 105 or greater.
(c)

Answer to Problem R7.6RE
0.0049
Explanation of Solution
Given:
Formula used:
Calculation:
The mean of the sampling distribution of the sample mean
The standard deviation of the sampling distribution of the sample mean
The z-score is
The corresponding probability using table
(d)
To find: the affect if the distribution of WAIS scores in the adult population was distinctly non-normal.
(d)

Answer to Problem R7.6RE
- Affected
- and (c) not affected
Explanation of Solution
The answer in (a) could be very different, because it is supposed that the population distribution was normal to find the probability.
The answer in (b) and (c) will not be very different, the reason is that the sample size is 30 or more and, by the central limit theorem, know that the sampling distribution is about normal even if the population distribution is not normal.
Chapter 7 Solutions
PRACTICE OF STATISTICS F/AP EXAM
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