# Thread: Another p-value-am I missing anything?

1. ## Another p-value-am I missing anything?

I can't figure out how to solve this one. Am I missing data or how should I go about it?

Problem 2.
An automatic bottling machine fills cola into two liter (2000 cc) bottles. A consumer advocate wants to test the null hypothesis that the average amount filled by the machine into a bottle is at least 2000 cc. A random sample of 40 bottles coming out of the machine was selected and the exact content of the selected bottles are recorded. The sample mean was 1999.6 cc. The population standard deviation is known from past experiences to be 1.30 cc. Compute the p-value for this test. Test the null hypothesis at the 5% significance level. Test the null hypothesis at the 1% significance level.

Solution in progress...
Data:
$\mu=2000 cc, n=40, \overline{x}=1999.6, \sigma=1.30 cc$

$\alpha_1=.05 \rightarrow Z_1=1.96.$ If $-1.96 < Z* < 1.96$, then we fail to reject the null hypothesis.

$\alpha_2=.01 \rightarrow Z_2=2.575.$ If $-2.575 < Z* < 2.575$, then we fail to reject the null hypothesis.

$H_0: ?$
$H_a: ?$

$Z*=\frac{\hat{p}-p_o}{\sqrt{\frac{p_o(1-p_o)}{n}}}$, but what is $\hat{p}$ and $p_o$ for this problem?

2. you are testing means, not proportions.

3. ## thanks!

Originally Posted by matheagle
you are testing means, not proportions.