A random sample of 139 forty-year-old men contains 26%smokers. Find the P-value for a test of the claim that thepercentage of forty year-old men that smoke is 22%

Question

anonymous · Answer

I can't find the right answer

amistre64 · Answer

isnt this:$$\dfrac{\hat p-p}{\sqrt{\large \frac{pq}{n}}}$$??

anonymous · Answer

Yes buti don't know how to solve it

amistre64 · Answer

$$\dfrac{.26-.22}{\sqrt{\large \frac{.22~.78}{139}}}$$
gives us a zscore to play with

amistre64 · Answer

hopefully i used the right phat and p

amistre64 · Answer

do you recall if we subtract the claim proportion, or the sample proportion?

amistre64 · Answer

i think we subtract the claim,  in which case -.22 is the way to go

amistre64 · Answer

that gives us a test statistic of 1.14

amistre64 · Answer

the claim is:  22% of 40yr smoke
therefore the counter claim is that:  22% do not smoke

this is a two tailed test.  so we double the results of a tail to get the P-value

amistre64 · Answer

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