Question 1

Solve the problem.
-A confidence interval for a population mean has a margin of error of 0.081. Determine the length of the confidence interval.

Accepted Answer

A) 0.007 
B) 0.081 
C) 0.041 
D) 0.162 
A) 0.007 
B) 0.081 
C) 0.041 
D) 0.162

Question 2

Find the requested confidence interval.
-The data below consists of the pulse rates (in beats per minute) of 32 students. Assuming $\sigma = 10.66$, obtain a $95.44 \%$ confidence interval for the population mean.
$\begin{array} { l l l l l l l l } 80 & 74 & 61 & 93 & 69 & 74 & 80 & 64 \ 51 & 60 & 66 & 87 & 72 & 77 & 84 & 96 \ 60 & 67 & 71 & 79 & 89 & 75 & 66 & 70 \ 57 & 76 & 71 & 92 & 73 & 72 & 68 & 74 \end{array}$

Accepted Answer

A) $70.65$ to $76.27$ beats per minute 
B)  $69.62$ to $77.14$ beats per minute 
C)  $68.55$ to $78.23$ beats per minute 
D)  $51.53$ to $95.26$ beats per minute 
A) $70.65$ to $76.27$ beats per minute 
B)  $69.62$ to $77.14$ beats per minute 
C)  $68.55$ to $78.23$ beats per minute 
D)  $51.53$ to $95.26$ beats per minute

Question 3

Write the word or phrase that best completes each statement or answers the question.
-Describe the steps involved in using the z-interval procedure to obtain a confidence interval for the population mean when $\sigma$  is known. Include a description of the preliminary data analysis. Why is preliminary data analysis needed?

Accepted Answer

Preliminary data analysis is needed to v

Question 4

Find the specified t-value.
-For a t-curve with df = 18, find the t-value having area 0.05 to its right.

Accepted Answer

A) 2.878 
B) 1.740 
C) 2.101 
D) 1.734 
A) 2.878 
B) 1.740 
C) 2.101 
D) 1.734

Solve the problem. -A confidence interval for a population mean has a margin of error of 0.081. Determine the length of the confidence interval.

Find the specified t-value. -For a t-curve with df = 18, find the t-value having area 0.05 to its right.

The Nature of Statistics

Organizing Data

Descriptive Measures

Probability Concepts

Discrete Random Variables

The Normal Distribution

The Sampling Distribution of the Sample Mean

Hypothesis Tests for One Population Mean

Inferences for Two Population Means

Inferences for Population Standard Deviations

Inferences for Population Proportions

Chi-Square Procedures

Descriptive Methods in Regression and Correlation

Inferential Methods in Regression and Correlation

Analysis of Variance Anova

Filters

Exam 8: Confidence Intervals for One Population Mean