An inspector inspects large truckloads of potatoes to determine the proportion p in the shipment with major defects prior to using the potatoes to make potato chips. Unless there is clear evidence that this proportion p is less than 0.10, he will reject the shipment. He will test the hypotheses H0: p = 0.10, Ha: p < 0.10. He selects an SRS of 200 potatoes from the more than 5000 potatoes on the truck. Suppose that 12 of the potatoes sampled are found to have major defects. The P-value of this test is:

Respuesta :

Answer:

[tex]z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}[/tex] (1)  

Replacing the info given we got:

[tex]z=\frac{0.06-0.10}{\sqrt{\frac{0.10(1-0.10)}{200}}}=-1.89[/tex]  

And the p value would be given by:

[tex]p_v =P(z<-1.89)=0.0294[/tex]  

Step-by-step explanation:

Information given

n=200 represent the random sample taken

X=12 represent the potatoes with major defects

[tex]\hat p=\frac{12}{200}=0.06[/tex] estimated proportion of potatoes with major defects

[tex]p_o=0.10[/tex] is the value that we want to test

z would represent the statistic

[tex]p_v[/tex] represent the p value

Hypothesis to test

We want to check if the true proportion is less than 0.10 so then the system of hypothesis are:  

Null hypothesis:[tex]p\geq 0.1[/tex]  

Alternative hypothesis:[tex]p < 0.10[/tex]  

The statistic is given by:

[tex]z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}[/tex] (1)  

Replacing the info given we got:

[tex]z=\frac{0.06-0.10}{\sqrt{\frac{0.10(1-0.10)}{200}}}=-1.89[/tex]  

And the p value would be given by:

[tex]p_v =P(z<-1.89)=0.0294[/tex]  

Considering the hypothesis tested, the p-value is of 0.0294.

The null hypothesis is:

[tex]H_0: p = 0.1[/tex]

The alternative hypothesis is:

[tex]H_a: p < 0.1[/tex]

The test statistic is given by:

[tex]z = \frac{\overline{p} - p}{\sqrt{\frac{p(1-p)}{n}}}[/tex]

In which:

  • [tex]\overline{p}[/tex] is the sample proportion.
  • p is the proportion tested at the null hypothesis.
  • n is the sample size.

For this problem, the parameters are:

[tex]p = 0.1, n = 200, \overline{p} = \frac{12}{200} = 0.06[/tex]

The value of the test statistic is:

[tex]z = \frac{\overline{p} - p}{\sqrt{\frac{p(1-p)}{n}}}[/tex]

[tex]z = \frac{0.06 - 0.1}{\sqrt{\frac{0.1(0.9)}{200}}}[/tex]

[tex]z = -1.89[/tex]

The p-value for this test is the probability of finding a sample proportion of 0.06 or below, which is the p-value of z = -1.89.

  • Looking at the z-table, z = -1.89 has a p-value of 0.0294.

A similar problem is given at https://brainly.com/question/24166849