pls help immediately! only answer if you know how to do this! giving extra points bc i really need this !

Several years ago, 50% of parents who had children in grades K-12 were satisfied with the quality of education the students r

galina1969 [7]

Answer:

The 95% confidence interval for the proportion of parents that are satisfied with their children's education is (0.4118, 0.4618). 0.5 is not part of the confidence interval, so this represents evidence that parents' attitudes toward the quality of education have changed.

Step-by-step explanation:

We have to see if 50% = 0.5 is part of the confidence interval.

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

For this problem, we have that:

$n = 1095, \pi = \frac{478}{1095} = 0.4365$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a pvalue of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.4365 - 1.96\sqrt{\frac{0.4365*0.5635}{1095}} = 0.4118$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.4365 + 1.96\sqrt{\frac{0.4365*0.5635}{1095}} = 0.4612$

The 95% confidence interval for the proportion of parents that are satisfied with their children's education is (0.4118, 0.4618). 0.5 is not part of the confidence interval, so this represents evidence that parents' attitudes toward the quality of education have changed.

5 0

3 years ago

For the following questions use f(x) = 2x + 5<br> Solve f(x) = 11

Eva8 [605]

Answer:

2

Step-by-step explanation:

8 0

3 years ago

Theo made a donation to a charity. His grandfather agreed to add $4.00 to Theo's donation amount and then donate half of that su

miss Akunina [59]

So you have to solve for "donation" - so let's call that X. And the things we know are what the grandfather donated, as a function - meaning based upon - Theo's donation. We'll call that Y.

So Y is equal to 1/2 of $4 plus Theo's donation...... 0.5*(x+4).

So... 4.25 = 0.5(X+4), solving for X

4.25=0.5x + 2

-2 -2

2.25=0.5x - divide each side by 0.5 to get x alone.

x = 4.50

Plugging back in:

(4.50 + 4.00)*0.5 = 4.25!

8 0

4 years ago

Read 2 more answers

Which is greater -9/6 or 3/-2

tigry1 [53]

Answer:

Step-by-step explanation:

-9/6 im not sure so dont get mand if im wrong

6 0

3 years ago

25% of the accountants in a business are female. if there are 360 accountants altogether how many accountants are female ? round

Darina [25.2K]

360 × 25% = 90 female accountants

3 0

4 years ago