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zella21
May 14, 2011, 03:09 PM
Suppose the proportion of elements of a population that possess a certain characteristic is .60. Assuming that n/N is less than or equal to .05, the probability that the sample proportion for a sample of 100 elements drawn from this population is between .62 and .67 is approximately:

For a continuous random variable x, the population mean and the population standard deviation are 100 and 20 respectively. Assuming n/N is less than or equal to .05, the standard deviation of the sampling distribution of the sample mean for a sample of 16 elements taken from this population is

A sample of 1000 families selected from a large city showed that 18% of them make $100,000 or more per year. The 99% confidence interval for the proportion of all families living in this city who make $100,000 or more per year is

In a 1997 poll of 236 male, married, upper-level managers conducted by Joy Schneer and Frieda Reitman for Fortune magazine, 28% of the men stated that their wives worked either full-time or part-time (Fortune, March 17, 1997). What are the boundaries for a 99% confidence interval for p, the proportion of all male, married, upper-level managers whose wives work?

In a sample of 500 items produced by a machine, the quality control staff found 7% to be defective. The 95% confidence interval for the proportion of defective items in all items produced by this machine is

A random sample of 16 life insurance policy holders showed that the mean value of their life insurance policies is $200,000 with a standard deviation of $50,000. Assume that the values of life insurance policies for all such policy holders have an approximate normal distribution. The 99% confidence interval for the mean value of all life insurance policies is

For a continuous random variable x, the population mean and the population standard deviation are 80 and 15 respectively. You extract a sample of 25 elements from this population. The mean of the sampling distribution of the sample mean is

For a continuous random variable x, the population mean and the population standard deviation are 54 and 12 respectively. You extract a sample of 36 elements from this population. The mean of the sampling distribution of the sample mean is:

What is the area in the left tail of the chi-square distribution for a value of 27.4884 and 15 degrees of freedom?

In a test of hypothesis, the null hypothesis is that the population mean is equal to 140 and the alternative hypothesis is that the population mean is less than 140. A sample of 100 elements selected from this population produced a mean of 134 and a standard deviation of 27.5. What is the approximate p-value for this test?

The manager of a fund that provides loans for college students has estimated that the average monthly loan repayment for students borrowing from the fund is $75.00. You are to test this estimate. You take a sample of 20 students and find that the mean monthly payment is $69.46 with a standard deviation of $9.78. Which of the following statements is true about this test?

A sample of 14 elements selected from a population produced a mean of 57 and a standard deviation of 7. Another sample of 20 elements selected from another population produced a mean of 52 and a standard deviation of 10. Assume that the two populations are normally distributed and the standard deviations of the two populations are not equal. What is the 90% confidence interval for the difference between the two population means?

A sample of 12 elements selected from a population produced a mean of 84 and a standard deviation of 16. Another sample of 15 elements selected from another population produced a mean of 72 and a standard deviation of 14. Assume that the two populations are normally distributed and the standard deviations of the two populations are not equal. What is the 99% confidence interval for the difference between the two population means?

A sample of 16 elements selected from a population produced a mean of 26 and a standard deviation of 4. Another sample of 18 elements selected from another population produced a mean of 36 and a standard deviation of 3. Assume that the two populations are normally distributed and the standard deviations of the two populations are not equal. What is the 95% confidence interval for the difference between the two population means?

A sample of 500 school teachers, who are married, showed that 42% of them hold a second job to supplement their incomes. Another sample of 400 school teachers, who are single, showed that 35% of them hold a second job to supplement their incomes. What is the 95% confidence interval for the difference between the proportions of married and single school teachers who hold a second job to supplement their incomes?

According to a Louis Harris survey, 53% of female drivers and 43% of male drivers never speed. Suppose these results stem from samples of 1000 female drivers and 1200 male drivers, respectively. What is the 99% confidence interval for the difference between the proportions of all female and all male drivers who never speed?

In a sample of 800 male job-holders, 69% said that they are satisfied with their jobs. In another sample of 900 female job-holders, 61% said that they are satisfied with their jobs. The 97% confidence interval for the difference between the proportions of all male and all female job-holders who will say that they are satisfied with their jobs is:

Each employee of a large company is encouraged to contribute, through payroll deduction, to an international charity. Annual contributions per employee follow (approximately) a normal distribution. You take a sample of 25 employees and find that the sample mean annual contribution per employee is $502 with a standard deviation of $18. What are the boundaries for a 99% confidence interval for the population mean?


if you look at them they are all different and there is no more information to give you

ballengerb1
May 14, 2011, 03:39 PM
zella why have you posted the same question over 20X in the past few minutes.

Fr_Chuck
May 14, 2011, 03:48 PM
It appeared you posted the same question since you gave all of them the same name. I renamed your question, since its name was lost in the merge.

If you had taken time to read the rules you find we do not do your homework, if you wish to give us the answers you think, we can discuss if your answer if good or bad.

I have merged them, since no one is going to do all of your homework for you here.

Unknown008
May 15, 2011, 01:54 AM
What a haul! :eek: