SOLUTION: Please help me with my homework questions on confidence intervals: in 1965, 44% of people never smoked. In 2006 a national survey of 1205 people, 615 never smoked cigarettes. 1)

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Question 387906: Please help me with my homework questions on confidence intervals:
in 1965, 44% of people never smoked. In 2006 a national survey of 1205 people, 615 never smoked cigarettes.
1) A 96% confidence interval for the proportion of people who never smoked in 2006 is:
I said 0.470-0.551. Is this correct?
2)Suppose you wish to find out if there was a change from 1965-2006. What would be an appropriate hypothesis?
I said ho: p= 0.44, ha: p > 0.44.
Is this correct?
3)The p-value of the test hypothesis for 5 rooms that a carpeted with a mean of 184 and a standard deviation of 27.0 and 5 uncarpeted rooms with a mean of 172 and standard deviation of 17.9 is?
I said between .01-.05
Is this correct?
Answer by jim_thompson5910(35256) (Show Source):
You can put this solution on YOUR website!
1)

You should have gotten (0.48, 0.53) as your 96% CI, what did you get for z and p?

2)

Your null hypothesis is correct, but your alternative hypothesis should be

:

3)

I'm not understanding the question. Are you comparing these two means? Or is one mean a sample mean and the other a population mean? I'm sure there's more to this problem.

If you're doing a significance test, then your p-value is actually much larger.