A random sample of 200 apples was taken from an orchard and 30 were found rotten. Form a 99% confidence interval for the proportion of rotten apples in the orchard
n = sample size = number of apples = 200
x = number of rotten apples = 30
c = confidence level = 99% = 0.99
Proportion of rotten apples
The formula of a confidence interval for the proportion
Z - critical value at given confidence level.
alpha = 1 - c = 1 - 0.99 = 0.01
alpha/2 = 0.01/2 = 0.005
1- (alpha/2) = 1 - 0.005 = 0.995
Z critical value using z table for area 0.995 is 2.58
(0.084858, 0.215142) is the 99% confidence interval for the proportion of rotten apples in the orchard.
A random sample of 200 apples was taken from an orchard and 30 were found rotten....
Out of a random sample of 200 youth, 50 are found to be careless drivers. Out of a random sample of 400 adults, 64 are found to be careless drivers. a. Determine, at a 1% significance level, if there is good evidence that the proportion of youth who are careless drivers is different than the proportion of adults who are careless drivers b. Form a 99% confidence interval for the difference in proportion of youth and adults who are careless...
What proportion of JMU students like online courses? To estimate this, a random sample of 200 students was taken and found that 50 of them like online courses. (1) Are the assumptions for constructing a confidence interval for the population proportion satisfied? Explain.(2) Construct a 99% confidence interval for the population proportion of JMU students who like online courses.(3) What is the margin of error in (2) ?______________(4) Interpret the 99% confidence interval.
A random sample of 200 computer chips is obtained from one factory and 4% are found to be defective. Construct and interpret a 99% confidence interval for the percentage of all computer chips from that factory that are NOT defective.
A random sample of 870 people was taken from those who were selected to serve on a grand jury in Hidalgo County, Texas over an 11-year period of time. Out of the sample, 348 of them were Mexican-Americans. a. Use this sample data to construct a 99% confidence interval estimate of the proportion of grand jury members who were Mexican-Americans. Make sure to show all components necessary to construct the confidence interval. Round your final answer to 3 decinal places...
A random sample of 870 people was taken from those who were selected to serve on a grand jury in Hidalgo County, Texas over an 11-year period of time. Out of the sample, 348 of them were Mexican-Americans. a. Use this sample data to construct a 99% confidence interval estimate of the proportion of grand jury members who were Mexican-Americans. Make sure to show all components necessary to construct the confidence interval. Round your final answer to 3 decimal places....
A random sample of 870 people was taken from those who were selected to serve on a grand jury in Hidalgo County, Texas over an 11-year period of time. Out of the sample, 348 of them were Mexican-Americans. a. Use this sample data to construct a 99% confidence interval estimate of the proportion of grand jury members who were Mexican-Americans. Make sure to show all components necessary to construct the confidence interval. Round your final answer to 3 decimal places....
A sample of N = 30 individuals is taken and it is found that the mean commute time to work for these individuals is 35 minutes with a sample standard deviation of 10 minutes. Find a 99% confidence interval for the mean commute time to work.
1) From a random sample of 121 government employees it is found that 65 of them are males. Construct a 99% confidence interval for the proportion of males in government service.
Pg 417 6.47 For a hypothesis test H0: p = 0.3 Ha: p < 0.3 a random sample of size n 200 is taken and the sample proportion p = 0.21 (a) Determine whether it is appropriate to use the normal distribution to estimate the p-value. (b) If it is appropriate to use a normal distribution, complete the test for a significance level of 5% Pg 418 6.55 Home Field in Baseball 2009 There were 2430 Major League Baseball games played in 2009, and the home team won the...
In a sample of 140 high-pressure molds taken from the PATRICK cast company, 28 were found to have cracks resulting from improper heating of the mold. a) What is the point estimate of the proportion of all castings that have cracks? b) Find a 92% confidence interval for the true proportion of all castings that have cracks.