When testing a hypothesis about a single mean, if the sample size is 20, the population standard deviation is unknown, and the population is assumed to be a normal distribution, the correct test statistic to use is ___________. A. z-test B. t-test

In looking at the results of a standardized exam, 72% of those taking the test choose the correct answer on the first question. Answer the following for 400 test takers who are to be randomly chosen. After taking the sample and administering the test, 320 of the test takers answer the first question correctly.   The sample proportion is ____________________.         Find the mean and variance for the distribution of sample proportions from samples of size n = 400.   Mean: __________________       Variance: ___________________                 The probability is ____________________ for taking another random sample of size n = 400 test takers and more than 75% of them getting the correct answer on this question.

Select all true statements below (Multiple or none can be true). With a large, representative sample, the histogram of the sample data will follow the normal curve closely. If two lists of numbers have exactly the same average of 50 and SD of 10, then the percentage of entries between 40 and 60 must be exactly the same for both lists. Half of a list of numbers is always below its average. The median and average of a list of numbers are not necessarily close together.

You take a random sample of n = 900 observations from a population with a mean of 100 and a standard deviation of 10. What's the largest value of x you would expect to find?       A. 108  B. 101  C. 100  D. 110

The mean number of eggs per person eaten in the United States is 252 and the standard deviation is 68. Do college students eat more than the average? The 45 college students surveyed averaged 281 eggs per person. What can be concluded at the 0.05 level of significance? H0: = 252 Ha: _____________ 252 Test statistic: __________    p-Value =__________                    Reject/Fail to reject H0?______________         Conclusion: There is____________   evidence to make the conclusion that the population mean number of eggs consumed college students per year is more than 252 eggs per student per year. p-Value Interpretation: If the mean number of eggs consumed per year for college students is equal to_________  and if another study was done with a new randomly selected group of 45 college students, then there is a ____________ percent chance that the average number of eggs consumed per year for this new sample would be greater than_____________        . Level of significance…

If a distribution of data follows a normal distribution, we would expect that the __________, and __________ are all equal.

Need help on a and finding the t and p value

need help with my homework question

Fill in the Blanks: Applying Chebyshev's Rule to this distribution, we estimate that 75% or more of women with metastatic breast cancer will survive between __________ and __________ years (2 standard deviations from the mean).

A  Find the standard error of the mean for each sampling situation (assuming a normal population).  (Round your answers to two decimal places). 1.  O=56, n=4 2. O=56, n=16 3.  O=56, n=64 B.  What happens to the standard error each time you quadruple the sample size? The standard error is ________ by half.