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mherr
May 4, 2009, 05:09 PM
880 randomly chosen people surveyed. 493 of them admitted to chewing gum. If we use a signifagant level of 0.01, can we conclude that a majority of people chew gum?

mherr
May 5, 2009, 12:54 AM
880 randomly chosen people surveyed. 493 of them admitted to chewing gum. If we use a signifagant level of 0.01, can we conclude that a majority of people chew gum?

i get:

\hat p=493/880 the test statistic is {\hat p -.5\over \sqrt{(.5)(.5)\over 880}}

I put \hat p=493/880 into the formula:

{(443/880) -.5\over \sqrt{(.5)(.5)\over \880}}=3.573

is this correct and where do i go from here? I don't understand how the significance level has anything to do with the problem


also, the bottom of the equation is supposed to be the square root of (.5^2)/880

galactus
May 5, 2009, 05:28 AM
You have the correct test statistic.

We have:

H_{0}: p<=.5

H_{a}: p>.5, claim

there must be something wrong with LaTex this morning. It is not displaying right, so I done away with the tags

The critical value is 2.3263

Since the test stat is inside the rejection region we reject the null hypothesis.

Therefore, we can say the majority chew gum.

The significance level is used to find the critical value of 2.3263.

Look up .99 in the body of the z table and see that its z-score is 2.33

Unknown008
May 5, 2009, 09:58 AM
there must be something wrong with LaTex this morning. It is not displaying right, so I done away with the tags

You sometimes have to use spaces so that the program doesn't confuse with commands... that's my opinion.