(a)
To find: the standardized test statistic and P-value in each setting and make an appropriate conclusion for part (a)
(a)

Answer to Problem R9.3RE
t= -1.311
Or P=0.19622
There is no enough convincing proof that the true mean height of this year’s female graduates from the large high school differs from the national average.
Explanation of Solution
Given:
Claim is that the mean is different from 64.2
Calculation:
The claim is either the null hypothesis or the alternative hypothesis. The null hypothesis statement is that the population mean is equal to the value given in the claim. If the null hypothesis is the claim, then the alternative hypothesis statement is the opposite of the null hypothesis.
The P-value is the probability of getting the value of the test statistic, or a value more extreme, assuming that the null hypothesis is true.
Command Ti83/84- calculator: 2*tcdf (-1E99, -1.311, 47) which would return a P-value of 0.19622. Note: it could replace -1E99 by any other very small negative number.
If the P-value is lesser than the significance level
There is no enough convincing proof that the true mean height of this year’s female graduates from the large high school differs from the national average.
(b)
To find: the standardized test statistic and P-value in each setting and make an appropriate conclusion for part (b)
(b)

Answer to Problem R9.3RE
Z=2.07
P=0.0192
There is enough convincing proof that the true proportion of students in their school who have played in the rain is greater than 0.25.
Explanation of Solution
Given:
Formula used:
Calculation:
The claim is either the null hypothesis or the alternative hypothesis. The null hypothesis statement is that the population proportion is equal to the value given in the claim. If the null hypothesis is the claim, then the alternative hypothesis statement is the opposite of the null hypothesis.
The sample proportion is
The test-statistic is
The P-value is the probability of getting the value of the test statistic or a value more extreme, when the null hypothesis is true. Find the P-value using the normal probability table
If the P-value is lesser than the significance level
There is enough convincing proof that the true proportion of students in their school who have played in the rain is greater than 0.25.
Chapter 9 Solutions
PRACTICE OF STATISTICS F/AP EXAM
Additional Math Textbook Solutions
Calculus for Business, Economics, Life Sciences, and Social Sciences (14th Edition)
A First Course in Probability (10th Edition)
Elementary Statistics: Picturing the World (7th Edition)
University Calculus: Early Transcendentals (4th Edition)
A Problem Solving Approach To Mathematics For Elementary School Teachers (13th Edition)
Calculus: Early Transcendentals (2nd Edition)
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