Confidence interval for mean all time for all timeport

Assignment Help Basic Statistics
Reference no: EM13128599

Talk Time on a Cell Phone Suppose Motorola wishes to estimate the mean "talk time" for its Timeport P8160 digital phone before the battery must be recharged. In a random sample of 40 phones, the sample mean talk time was 315 minutes with a standard deviation of 24 minutes.

(a) Why can we say that the sampling distribution of x is approximately normal?

(b) Construct a 94% confidence interval for the mean "talk time" for all Timeport P8160 digital phones.

(c) Construct a 98% confidence interval for the mean "talk time" for all Timeport P8160 digital phones.

Reference no: EM13128599

Questions Cloud

Social functions : Discuss the social functions/dysfunctions of deviance. Based on numerous theories, can society ever be free of deviance? Why or why not?
What is the molecular weight of the unknown : A 5.50 g sample of an unknown is dissolved in 251. g of benzene. The freezing point of the solution is 1.02 C below the normal freezing point of pure benzene.
Why is depreciation for income tax purposes an important : Why is depreciation for income tax purposes an important concern of taxpayers and how does tax depreciation differ from financial accounting depreciation?
What are corporate dividends : What are corporate dividends and how are they distributed and accounted for? Provide a discussion of all potential scenarios and the relevant accounting requirements.
Confidence interval for mean all time for all timeport : The sample mean talk time was 315 minutes with a standard deviation of 24 minutes. Why can we say that the sampling distribution of x is approximately normal?
What will be the equilibrium output for the industry : What will be the equilibrium price? What will be the equilibrium output for the industry? For each firm? What will profit or loss be per unit? Per firm? Will this industry expand or contract in the long run?
How can firms use transfer prices strategically : What role does GAAP play in how firms determine transfer prices?
Standard theorems on trigonometric limits : Using the definition of the derivative and any standard limiting theorems, show that the derivative of (sinx)^2 is sin(2x).
The fictional critique on art critique : read the fictional critique below. Then answer the subsequent questions. Art Critique

Reviews

Write a Review

Basic Statistics Questions & Answers

  Percent of internet users who download music

Using a significance test, evaluate whether or not there has been a change in the percent of Internet users who download music. Provide all details for the test. (Round your value for z to two decimal places. Round your P-value to four decimal pla..

  Determining mutually exclusive events

Events A and B are mutually exclusive events defined on common sample space. If P (A) 0.5 and P (A or B) = 0.70, determine P (B).

  Value of the standard normal random variable

If the value of the standard normal random variable Z is positive, then the original score is where in relationship to the mean?

  Computing random sample and confidence interval

You are given the sample mean and the sample deviation, Use this information to construct the 90% and 95% confidence intervals for the population mean. Which interval is wider?

  Confi dence interval to test your null hypothesis

Enter the data into R, and calculate the means for placebo and epinephrine. Find a 95% confi dence interval for the mean diff erence in cholesterol levels between the placebo and epinephrine. Use the confi dence interval to test your null hypothes..

  Mean systolic blood pressure for population african-american

We wish to know if, on the basis of these data, we may conclude that the mean systolic blood pressure for a population of African-American men is greater than 140.

  An experiment consists of making 80 telephone calls

In textile industry, a manufacturer is interested in the number of blemishes or flaws occurring in each 100 feet of material. Of the following probability distributions, the one that most applies to this situation is the.

  Test of a proportion

What is a test of a proportion and give an example. What test do you use when one sample is small and the other large?

  Determine the probability sample identifications correct

What is the probability that the sample will have between 50% and 60% of the identifications correct? What is the probability that the sample percentage of correct identifications is greater than 65%?

  Number of occurrences of an event

The random variable x, which is the number of occurrences of an event over an interval of ten minutes. It can be assumed that the probability of an occurrence is the same in any two time periods of an equal length.

  Standard deviations through the mean

The random variable x has a normal distribution with mean=30 and standard deviation = 30. Find the probability that x assumes a value more than two standard deviations from its mean more than three standard deviations from the mean.

  Simplifying a product of radical expressions

Simplify a product of radical expressions. Assume that all variables represent positive real numbers

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd