/*! 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 55 Determine the value of \(z\) so ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Determine the value of \(z\) so that the area under the standard normal curve a. in the right tail is \(.0500\) b. in the left tail is \(.0250\) c. in the left tail is \(.0100\) d. in the right tail is \(.0050\)

Short Answer

Expert verified
The corresponding \(z\) values for the areas under the standard normal curve are: a. \(1.64\), b. \(-1.96\), c. \(-2.33\), and d. \(2.57\).

Step by step solution

01

Understand the standard normal distribution

The standard normal distribution is a special case of the normal distribution where the mean is zero and the standard deviation is 1. The skewness and kurtosis are also standardized, resulting in a bell-shaped graph or curve. The total area under this curve is 1.
02

Interpret the request for right tail or left tail

The 'right tail' refers to the part of the distribution curve that lies to the right of the \(z\) value, while the 'left tail' refers to the part of the curve that lies to the left of the \(z\) value. The right tail includes all values greater than \(z\), while the left tail includes all values less than \(z\). In a standard normal distribution curve, the area in the right tail corresponds to the probability that a randomly chosen standard normal variable is greater than \(z\). Similarly, the area in the left tail corresponds to the probability that a random standard normal variable is less than \(z\).
03

Lookup the z-table in reverse or use the inverse Z-table function.

Normally, we use the table of standard normal distribution or z-table to find the probability given a \(z\) value. However, in this case, we have the area under the curve (probability) specified, and we need to find the corresponding \(z\) value(s). Thus, we need to do a reverse lookup of the z-table or use the inverse function of Z-table lookup on software programs such as Excel, MATLAB or R.
04

Find the corresponding \(z\) value for each area.

a. For right tail area \(.0500\), the \(z\) value is approximately \(1.64\) (as the cumulative probability on left is \(.9500\)).b. For left tail area \(.0250\), the \(z\) value is approximately \(-1.96\) (as the cumulative probability on left is \(.0250\)).c. For left tail area \(.0100\), the \(z\) value is approximately \(-2.33\) (as the cumulative probability on left is \(.0100\)).d. For right tail area \(.0050\), the \(z\) value is approximately \(2.57\) (as the cumulative probability on left is \(.9950\)).

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

At Jen and Perry Ice Cream Company, a machine fills 1-pound cartons of Top Flavor ice cream. The machine can be set to dispense, on average, any amount of ice cream into these cartons. However, the machine does not put exactly the same amount of ice cream into each carton; it varies from carton to carton. It is known that the amount of ice cream put into each such carton has a normal distribution with a standard deviation of 18 ounce. The quality control inspector wants to set the machine such that at least \(90 \%\) of the cartons have more than 16 ounces of ice cream. What should be the mean amount of ice cream put into these cartons by this machine?

According to the records of an electric company serving the Boston area, the mean electricity consumption for all households during winter is 1650 kilowatt-hours per month. Assume that the monthly electricity consumptions during winter by all households in this area have a normal distribution with a mean of 1650 kilowatt-hours and a standard deviation of 320 kilowatt-hours. a. Find the probability that the monthly electricity consumption during winter by a randomly selected household from this area is less than 1950 kilowatt- hours. b. What percentage of the households in this area have a monthly electricity consumption of 900 to 1300 kilowatt-hours?

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

According to the U.S. Employment and Training Administration, the average weekly unemployment benefit paid out in 2008 was \(\$ 297\) (http://www.ows.doleta.gov/unemploy/hb394.asp). Suppose that the current distribution of weekly unemployment benefits paid out is approximately normally distributed with a mean of \(\$ 297\) and a standard deviation of \(\$ 74.42\). Find the probability that a randomly selected American who is receiving unemployment benefits is receiving a more than \(\$ 400\) per week b. between \(\$ 200\) and \(\$ 340\) per week

A machine at Keats Corporation fills 64 -ounce detergent jugs. The machine can be adjusted to pour, on average, any amount of detergent into these jugs. However, the machine does not pour exactly the same amount of detergent into each jug; it varies from jug to jug. It is known that the net amount of detergent poured into each jug has a normal distribution with a standard deviation of \(.35\) ounce. The quality control inspector wants to adjust the machine such that at least \(95 \%\) of the jugs have more than 64 ounces of detergent. What should the mean amount of detergent poured by this machine into these jugs be?

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.