Warning: foreach() argument must be of type array|object, bool given in /var/www/html/web/app/themes/studypress-core-theme/template-parts/header/mobile-offcanvas.php on line 20

Consider two normal distributions, one with mean -4 & standard deviation 3 or the one with mean -4 and standard deviation 6. Answer true or false to each statement and explain your answers

a. The two normal distributions have same spread

b. The two normal distributions are centred at the same place.

Short Answer

Expert verified

A. The two normal distributions have same spread : False

B. The two normal distributions are centred at the same place : True

Step by step solution

01

Spread Concept and False

Spread is a measure of variability of data around the mean, it indicates on average that how scattered the other values are around mean.

Standard Deviation is a statistical measure of dispersion. It is the under root of average squared deviations around mean.

So as the standard deviation of both distributions are unequal, ie 3 and 6 respectively. So, they don't have same spread

02

Centre Concept & True

Centre of the distribution denotes the measures of central tendency, which is most prominently arithmetic mean.

As the means of distributions are equal ie -4, so there centre is equal.

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 Vaia!

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

Notation What does the notation Zฮฑ indicate?

Low Birth Weight The University of Maryland Medical Center considers โ€œlow birth weightsโ€ to be those that are less than 5.5 lb or 2495 g. Birth weights are normally distributed with a mean of 3152.0 g and a standard deviation of 693.4 g (based on Data Set 4 โ€œBirthsโ€ in Appendix B).

a. If a birth weight is randomly selected, what is the probability that it is a โ€œlow birth weightโ€?

b. Find the weights considered to be significantly low, using the criterion of a birth weight having a probability of 0.05 or less.

c. Compare the results from parts (a) and (b).

Basis for the Range Rule of Thumb and the Empirical Rule. In Exercises 45โ€“48, find the indicated area under the curve of the standard normal distribution; then convert it to a percentage and fill in the blank. The results form the basis for the range rule of thumb and the empirical rule introduced in Section 3-2.

About______ % of the area is between z = -3 and z = 3 (or within 3 standard deviation of the mean).

Quarters After 1964, quarters were manufactured so that their weights have a mean of5.67 g and a standard deviation of 0.06 g. Some vending machines are designed so that you canadjust the weights of quarters that are accepted. If many counterfeit coins are found, you cannarrow the range of acceptable weights with the effect that most counterfeit coins are rejectedalong with some legitimate quarters.

a. If you adjust your vending machines to accept weights between 5.60 g and 5.74 g, what percentage of legal quarters are rejected? Is that percentage too high?

b. If you adjust vending machines to accept all legal quarters except those with weights in the top 2.5% and the bottom 2.5%, what are the limits of the weights that are accepted?

In Exercises 9โ€“12, find the indicated IQ score and round to the nearest whole number. The graphs depict IQ scores of adults, and those scores are normally distributed with a mean of 100 and a standard deviation of 15 (as on the Wechsler IQ test).

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.

Sign-up for free