# Statistics and Margin of Error

I really need help with these questions by the end of the day thank you sooo much in advance margin of error means all except a) the difference between sample mean> and population mean b) the maximum expected sampling error c) we expect sample mean to be within this distance from population mean d) we expect sampling error to be no more than this number

The mean annual income for adult women in one city is > and the standard deviation of the incomes is > The distribution of incomes is skewed to the right. For samples of size 30, which of the following statements best describes the sampling distribution of the mean?

a)sample mean> is approximately normally distributed.

b)sample mean> is normally distributed.

c)Nothing can be said about the distribution of sample mean >.

d)The distribution of sample mean > is skewed to the right.

Let x represent the number which shows up when a balanced die is rolled. Then x is a random variable with a uniform distribution. Let sample mean > denote the mean of the numbers obtained when the die is rolled 3 times. Which of the following statements concerning the sampling distribution of the mean, sample mean> , is true?

a)sample mean> has a uniform distribution.

b)sample mean> is normally distributed.

c)sample mean> is approximately normally distributed.

d)None of the above statements is true.

The heights of adult women in the U.S are normally distributed. Let > denote the mean height for a random sample of 4 women. For samples of size 4, which of the following statements concerning the sampling distribution of the mean is true? a)sample mean> is normally distributed.

b) sample mean> is approximately normally distributed.

c) sample mean> has a uniform distribution.

d)None of the above statements is true.

The mean height for a population is and the standard deviation is Let denote the mean height for a sample of people picked randomly from the population. True or false, the standard deviation of for samples of size 30 is greater than the standard deviation of for samples of size 20? True or False

The mean height for a population is 65 inches and the standard deviation is Let A and B denote the events described below.

Event A: The height of a randomly selected person will be within of the population mean. Event B: The mean height of a random sample of 16 people will be within of the population mean.

True or false, the probability of event A is greater than the probability of event B?

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What have you done so far? – Chris Taylor Jan 22 '12 at 17:46
I completed the questions but I think my answers are wrong – user23440 Jan 22 '12 at 18:59
What are your answers? [[Aside: the reason that you haven't got any responses yet is because it looks like you're asking us to do your homework for you and you haven't demonstrated any effort to solve the problems yourself. Also, you are asking multiple questions at once. You will get a better response if you make your questions specific, focused, and you clearly lay out what work you've already done.]] – Chris Taylor Jan 22 '12 at 19:01
1c,2d,3c,4a,5 True 6,False...I have no idea if they are right,i did what i think is correct – user23440 Jan 22 '12 at 19:02
ok,didn't know the questions was interpreted like that this is my first statistics class and these are the only questions i just don't get besides the text book,youtube,and sitting at my computer for 5 hrs straight trying to do it,but thank you – user23440 Jan 22 '12 at 19:50