standardized exam's scores are normally distributed. In a recent year, the mean test score was 1515 and the standard deviation was 316. The test scores of idents selected at random are 1920, 1260, 2260, and 1390. Find the z-scores that correspond to each value and determine whether any of the values are un ne z-score for 1920 is Cound to two decimal places as needed.) ne z-score for 1260 is Round to two decimal places as needed.) he z-score for 2260 is Round to two decimal places as needed.) The z-score for 1390 is Round to two decimal places as needed.) Mhich yoluor if any are unusual? Select the correct choice below and if necessary, fill in the answer box within your choice.

MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
icon
Related questions
Question
### Understanding Z-Scores in Normally Distributed Exam Scores

In a recent exam, a standardized test scores are normally distributed. The mean test score was 1515, and the standard deviation was 316. We will calculate the z-scores for four given student scores: 1920, 1260, 2260, and 1390. Then, we will determine whether any of these scores are unusual.

**Problem Statement:**
Given the following information:
- Mean (μ) = 1515
- Standard Deviation (σ) = 316

Calculate the z-scores for the specified test scores and determine whether any of the values are unusual.

#### Z-Score Formula
The z-score for a data point \( x \) can be calculated using the formula:
\[ z = \frac{x - \mu}{\sigma} \]
where \( x \) is the test score, \( \mu \) is the mean, and \( \sigma \) is the standard deviation.

#### Calculate Z-Scores
1. **The z-score for 1920 is \( \_\_ \):**
   \[ z = \frac{1920 - 1515}{316} \]
   (Round to two decimal places as needed.)

2. **The z-score for 1260 is \( \_\_ \):**
   \[ z = \frac{1260 - 1515}{316} \]
   (Round to two decimal places as needed.)

3. **The z-score for 2260 is \( \_\_ \):**
   \[ z = \frac{2260 - 1515}{316} \]
   (Round to two decimal places as needed.)

4. **The z-score for 1390 is \( \_\_ \):**
   \[ z = \frac{1390 - 1515}{316} \]
   (Round to two decimal places as needed.)

#### Determining Unusual Values
Z-scores are considered unusual if they are below -2 or above 2.

**Question: Which values, if any, are unusual? Select the correct choice below:**
- **A.** The unusual value(s) is/are \(\_\_\). (Use a comma to separate answers as needed.)
- **B.** None of the values are unusual.
Transcribed Image Text:### Understanding Z-Scores in Normally Distributed Exam Scores In a recent exam, a standardized test scores are normally distributed. The mean test score was 1515, and the standard deviation was 316. We will calculate the z-scores for four given student scores: 1920, 1260, 2260, and 1390. Then, we will determine whether any of these scores are unusual. **Problem Statement:** Given the following information: - Mean (μ) = 1515 - Standard Deviation (σ) = 316 Calculate the z-scores for the specified test scores and determine whether any of the values are unusual. #### Z-Score Formula The z-score for a data point \( x \) can be calculated using the formula: \[ z = \frac{x - \mu}{\sigma} \] where \( x \) is the test score, \( \mu \) is the mean, and \( \sigma \) is the standard deviation. #### Calculate Z-Scores 1. **The z-score for 1920 is \( \_\_ \):** \[ z = \frac{1920 - 1515}{316} \] (Round to two decimal places as needed.) 2. **The z-score for 1260 is \( \_\_ \):** \[ z = \frac{1260 - 1515}{316} \] (Round to two decimal places as needed.) 3. **The z-score for 2260 is \( \_\_ \):** \[ z = \frac{2260 - 1515}{316} \] (Round to two decimal places as needed.) 4. **The z-score for 1390 is \( \_\_ \):** \[ z = \frac{1390 - 1515}{316} \] (Round to two decimal places as needed.) #### Determining Unusual Values Z-scores are considered unusual if they are below -2 or above 2. **Question: Which values, if any, are unusual? Select the correct choice below:** - **A.** The unusual value(s) is/are \(\_\_\). (Use a comma to separate answers as needed.) - **B.** None of the values are unusual.
Expert Solution
steps

Step by step

Solved in 2 steps

Blurred answer
Similar questions
Recommended textbooks for you
MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc
Probability and Statistics for Engineering and th…
Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning
Statistics for The Behavioral Sciences (MindTap C…
Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning
Elementary Statistics: Picturing the World (7th E…
Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON
The Basic Practice of Statistics
The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman
Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman