A newspaper reported that the mean annual household income of its readers is GHC119,155. Assume this estimate of the mean annual household income is based on a sample of 80 households, and based on past studies, the population standard deviation is known to be o = GHC30,000. Develop a 95% confidence interval estimate of the population mean.

A newspaper reported that the mean annual household income of its readers is GHC119,155. Assume this estimate of the mean annual household income is based on a sample of 80 households, and based on past studies, the population standard deviation is known to be o = GHC30,000. Develop a 95% confidence interval estimate of the population mean.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

A random sample of 56 fluorescent light bulbs has a mean life of 645 hours and assume that the population standard deviation is 31 hours. Construct a 95% confidence interval for the population mean.
Assume researchers are trying to find out the mean concentration levels of a specific drug in a population of individuals’ blood during a clinical trail. The researchers find that the sample population of 30 has a mean concentration of 6.7 mcg/mL with a standard deviation of 1.3 mcg/ mL. Calculate a 95% confidence interval for the mean concentration level of the medication for the population’s blood and interpret it.
An SRS of 27 students at NYU gave an average height of 5.4 feet and a standard deviation of .1 feet. Find a 90% confidence interval for the mean height of students at NYU.
The lifetimes of a certain brand of battery are assumed to be normally distributed with a mean of 405 hours. Find the standard deviation of these battery lifetimes, if 90% of these batteries do not achieve a lifetime of 411 hours.
An agriculture researcher plants twenty five plots with a new variety of corn. The average yielded for these plots is x-bar = 150 bushels per acre. Assume that the yield per acre for the new variety of corn follows a normal distribution with unknown mean and standard deviation = 10 bushels per acre. A 90% Confidence interval for mean is?
A local health center noted that in a sample of 400 patients, the average sample age is 30 years with a population standard deviation of 4.4. Calculate the standard deviation of the sample mean of patients in the study. Provide a 95% confidence interval for the average age of all the patients who are referred to the health center by the hospital.
A college admissions director wishes to estimate the mean age of all students currently enrolled. In a random sample of 30 students the mean age is found to be 21.5 years. From past studies the population standard deviation at the college is known to be 1.2 years and the population is normally distributed. Construct a 95% confidence interval of the population median age.
The blenders produced by a company have a normally distributed life span with a mean of 8.2 years and a standard deviation of 0.8 years. What warranty should be provided so that the company is replacing about 6% of their blenders sold?
The following sample data are from a normal population: Sample size (n) = 25, Sample mean=14, Sample standard deviation=3.6 With 95% confidence, what is the margin of error for the estimation of the population mean?
During the past year, the flight times between two cities was reported to have a population standard deviation of 20 minutes. What would the margin of error be if a sample of 64 was used for estimating the mean flight time between the two cities and with a confidence level of 95%
The length of students' college careers at Anytown University is known to be normally distributed, with a mean length of 5.5 years and a standard deviation of 1.75 years. What is the lower quartile for the length of students' careers at Anytown University?
A study is conducted to find the mean life of a certain manufacturer's car batteries. A random sample of 34 batteries is selected and a mean of 47.5 months with a standard deviation of 7.3 months is found. Find a 95% confidence interval for the mean battery life.