/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 7 How do the width and height of a... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

How do the width and height of a normal distribution change when its mean remains the same but its standard deviation decreases?

Short Answer

Expert verified
When the standard deviation of a normal distribution decreases while the mean remains unchanged, the width of the distribution decreases, or in other words, the distribution becomes narrower. Simultaneously, the height of the distribution, or the peak, increases.

Step by step solution

01

Understand the Normal Distribution

A normal distribution is described by a bell shaped curve. The curve is symmetric around the mean, and is decided by two parameters: the mean (\(\mu\)) and the standard deviation (\(\sigma\)). The mean determines the center of the distribution whereas the standard deviation determines the spread around this mean. Larger the standard deviation, wider the spread and fatter the tails of the distribution. Conversely, smaller the standard deviation, narrower the spread and thinner the tails.
02

Analyze the Effect of Decreasing Standard Deviation

When the standard deviation (\(\sigma\)) decreases, the values in the distribution are less spread out. This causes reduction in the width of the distribution. The bell curve becomes narrower because values are closer to the mean.
03

Determine the Height Change

As the standard deviation decreases, the same amount of data is presented, but it is less spread out around the mean. This decrease in spread (width) needs to be compensated in order for the area under the curve to remain 1 (property of probability distribution). So, the height of the distribution increases when standard deviation decreases while keeping the mean constant.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

According to a Gallup poll, \(92 \%\) of Americans believe in God (Time, June 20,2011 ). Suppose that this result is true for the current population of adult Americans. What is the probability that the number of adult Americans in a sample of 500 who believe in God is a. exactly 445 b. at least 450 c. 440 to 470

For a continuous probability distribution, explain why the following holds true. $$ P(a

The Bank of Connecticut issues Visa and MasterCard credit cards. It is estimated that the balances on all Visa credit cards issued by the Bank of Connecticut have a mean of \(\$ 845\) and a standard deviation of \(\$ 270 .\) Assume that the balances on all these Visa cards follow a normal distribution. a. What is the probability that a randomly selected Visa card issued by this bank has a balance between \(\$ 1000\) and \(\$ 1440\) ? b. What percentage of the Visa cards issued by this bank have a balance of \(\$ 730\) or more?

Alpha Corporation is considering two suppliers to secure the large amounts of steel rods that it uses. Company A produces rods with a mean diameter of \(8 \mathrm{~mm}\) and a standard deviation of \(.15 \mathrm{~mm}\) and sells 10,000 rods for \(\$ 400\). Company B produces rods with a mean diameter of \(8 \mathrm{~mm}\) and a standard deviation of \(.12 \mathrm{~mm}\) and sells 10,000 rods for \(\$ 460\). A rod is usable only if its diameter is between \(7.8 \mathrm{~mm}\) and \(8.2 \mathrm{~mm}\). Assume that the diameters of the rods produced by each company have a normal distribution. Which of the two companies should Alpha Corporation use as a supplier? Justify your answer with appropriate calculations.

For the standard normal distribution, what is the area within two standard deviations of the mean?

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.