Ask Question, Ask an Expert

+1-415-315-9853

info@mywordsolution.com

Ask Statistics and Probability Expert

1) A normal population has a mean of 78 and the standard deviation of 6. You select a sample of 50.
find out the probability the sample mean is (Round z values to 2 decimal places andfinal answers to 4 decimal places):

(a) Less than 77.

(b) Between 77 and 79.

(c) Between 79 and 80.

(d) Greater than 80.

2) CRA CDs Inc. wants mean lengths of the "cuts" on a CD to be 150 seconds (2 minutes and 30 seconds). This would allow the disk jockeys to have plenty of time for commercials within each 10-minute segment. Suppose the distribution of the length of the cuts follows  normal distribution with the population standard deviation of 9 seconds. Assume we choose a sample of 24 cuts from various CDs sold by CRA CDs Inc.

(a) What could we say about shape of the distribution of the sample mean?

(b) What is the standard error of the mean? (Round your answer to 2 decimal places.)

(c) What percent of the sample means would be greater than 155 seconds? (Round your answer to 2 decimal places.)

(d) What percent of the sample means would be greater than 142 but less than 155 seconds? (Round your answer to 2 decimal places.)

3) The mean amount purchased by a typical customer at Churchill's Grocery Store is $21.00 with a standard deviation of $7.00. Assume the distribution of amounts purchased follows the normal distribution. For a sample of 42 customers, answer the following problems.

(a) What is the likelihood the sample mean is at least $22.50? (Round z value to 2 decimal places and final answer to 4 decimal places.)

(b) What is the likelihood the sample mean is greater than $20.00 but less than $22.50? (Round z value to 2 decimal places and final answer to 4 decimal places.)

(c) Within what limits would 99 percent of the sample means occur? (Round your answers to 2 decimal places.)

Statistics and Probability, Statistics

  • Category:- Statistics and Probability
  • Reference No.:- M92004

Have any Question? 


Related Questions in Statistics and Probability

Write a two-to three-page short paper 10 percent of your

Write a two-to three-page short paper (10 percent of your total grade) comparing and contrasting the presentation of a historical event by two different historians. Historians do not only provide accounts of events (them ...

An airline company is considering a new policy of booking

An airline company is considering a new policy of booking as many as 158 persons on an airplane that can seat only 160. (Past studies have revealed that only 90% of the booked passengers actually arrive for the flight.) ...

1 the correlation between self-esteem and shyness is -50

1. The correlation between self-esteem and shyness is -.50. Interpret this correlation. 2. Which is larger-a correlation of +.45 or a correlation of -.60? Explain.

You have been asked to evaluate the effects of a new

You have been asked to evaluate the effects of a new educational video that was developed to reduce racial prejudice among adolescents. You plan to administer a pretest measure of racial attitudes to 60 adolescent partic ...

Let x0 x1 x2nbspbe three vectors in rn prove that these

Let x 0 , x 1 , x 2  be three vectors in R n . Prove that these vectors are affine independent if and only if none of them is a convex combination of the other two.

Suppose we would like to determine if the typical amount

Suppose we would like to determine if the typical amount spent per customer for dinner at a new restaurant in town is more than $20.00. A sample of 49 customers over a three-week period was randomly selected and the aver ...

Subway footlongs are supposed to be 12 inches long you

Subway footlongs are supposed to be 12 inches long. You strongly suspect that Subway is up to its old tricks and is reducing the size of its delicious sandwiches. For your research, you randomly sample Subways and eat 10 ...

The mean number of medicine taken by a random sample of 26

The mean number of medicine taken by a random sample of 26 patients has a standard deviation of 3.1 medications. Assume the population is normally distributed Construct a 99% confidence interval for the population standa ...

1e model for a simple linear regression

1. Recall the model for a simple linear regression:  where  is Normally distributed with mean 0 and variance , where Cov( ) = 0 for all i, j and Cov(  = 0 for all i,j.A day trader wishes to develop a prediction model for ...

A gallup poll claims that at least 60 of adults in the

A Gallup poll claims that at least 60% of adults in the United States have used the Internet for shopping. In a survey of 1,025 randomly selected adults in the U.S., 678 said that they have used the Internet for shopping ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

WalMart Identification of theory and critical discussion

Drawing on the prescribed text and/or relevant academic literature, produce a paper which discusses the nature of group

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro