Answer:
We are 90% confident that the true proportion of teenagers who have used at least one informal element in school writing assignments is between 0.464 and 0.518
Step-by-step explanation:
We can begin finding the estimator for the proportion of interest:
![\hat p =\frac{442}{900}= 0.491](https://tex.z-dn.net/?f=%5Chat%20p%20%3D%5Cfrac%7B442%7D%7B900%7D%3D%200.491)
The confidence level is 90% , and the significance level would be given by
and
. And the critical value would be given by:
The confidence interval for the mean is given by the following formula:
Replacing the info given we got:
We are 90% confident that the true proportion of teenagers who have used at least one informal element in school writing assignments is between 0.464 and 0.518
Answer:
2(x + 4) - 1.
Step-by-step explanation:
The sum of a number and 4 = x + 4
Twice this = 2(x + 4)
So the answer is 2(x + 4) - 1.