Answer:
Step-by-step explanation:
Hello!
The confidence interval for the population proportion has the general structure of "sample proportion" ± "margin of error", this means that the interval is centered in the sample proportion.
To calculate the value of the sample proportion used to estimate this interval you have to do the following calculation:
The first step is to calculate the margin of error of the interval, which is half its amplitude:
[tex]d= \frac{Upperbond-Lowerbond}{2} = \frac{0.555-0.111}{2}= 0.222[/tex]
Then you choose one of the bonds and calculate the proportion:
If its the Upperbond you will subtract the margin of error, and if it's the Lower bond you will add it:
p= Upperbond - margin of error: 0.555-0.222= 0.333
-or-
p= Lowerbond + margin of error: 0.111+0.222= 0.333
Now you can rewrite the interval as asked:
0.333 ± 0.222
I hope it helps!
