A sample of 17 items was taken, and 5 of the units were found to be green. What is the 97% upper confidence limit(one-sided) for the percentage of green items

Respuesta :

Answer:

The 97% upper confidence limit for the proportion of green items is 0.502.

Step-by-step explanation:

We have to calculate a 97% upper confidence limit for the proportion.

The sample proportion is p=0.294.

[tex]p=X/n=5/17=0.294\\[/tex]

The standard error of the proportion is:

[tex]\sigma_p=\sqrt{\dfrac{p(1-p)}{n}}=\sqrt{\dfrac{0.294*0.706}{17}}\\\\\\ \sigma_p=\sqrt{0.01221}=0.11[/tex]

The critical z-value for a 97% upper confidence limit is z=1.881.

The margin of error (MOE) can be calculated as:

[tex]MOE=z\cdot \sigma_p=1.881 \cdot 0.11=0.208[/tex]

Then, the upper bound is:

[tex]UL=p+z \cdot \sigma_p = 0.294+0.208=0.502[/tex]

The 97% upper confidence limit for the proportion of green items is 0.502.