Basic Statistics: Tales of Distributions 10th Edition

Published by Cengage Learning
ISBN 10: 0-49580-891-1
ISBN 13: 978-0-49580-891-6

Chapter 4 - Exploring Data: Variability - Problems - Page 69: 4.16

Answer

See explanation

Work Step by Step

#### For Women: * $N = 60$ * $\sum X = \sum (\text{Height} \times \text{Frequency}) = 3852$ * $\sum X^2 = \sum (\text{Height}^2 \times \text{Frequency}) = 248898$ * $\bar{X} = \frac{3852}{60} = 64.2$ * $s^2 = \frac{248898 - \frac{3852^2}{60}}{59} = \frac{248898 - 247292.4}{59} \approx 7.06$ #### For Men: * $N = 60$ * $\sum X = 4200$ * $\sum X^2 = 295140$ * $\bar{X} = \frac{4200}{60} = 70.0$ * $s^2 = \frac{295140 - \frac{4200^2}{60}}{59} = \frac{295140 - 294000}{59} \approx 9.59$ _______ ### **Descriptive Statistics Summary** | Statistic | Women | Men | | --------------------------- | ----------- | ----------- | | Sample Size ($N$) | 60 | 60 | | Sum of Scores ($\sum X$) | 3,852 | 4,200 | | Sum of Squares ($\sum X^2$) | 248,898 | 295,140 | | Mean Height ($\bar{X}$) | **64.2 in** | **70.0 in** | | Sample Variance ($s^2$) | **7.06** | **9.59** | | Sample Std. Deviation ($s$) | **2.66 in** | **3.10 in** | --- ### **Interpretation** * **Men** in their 20s are, on average, taller than women by **5.8 inches**. * **Men's height distribution is more variable**, with a higher standard deviation (3.10 in vs. 2.66 in). * The sample variance confirms this broader spread in men's heights compared to women. * These findings could reflect natural biological differences and greater heterogeneity in male height.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.