HELP ME PLEASE!!!! I NEED HELP!!!!!

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

2 years ago

Oscar has received a $4,000 gift and is looking for a bank to start a savings account. Which option

hoa [83]

Answer:

The best option for him would be a real interest rate of 5%.

Step-by-step explanation:

The nominal interest rate is the one that represents the percentage of increase of the money that is in a certain investment, without discounting the depreciation due to inflation or the payment of taxes.

On the other hand, the real interest rate is the one that represents the real increase in the money invested, after discounting inflation and any taxes to be paid.

Therefore, the best option for Oscar would be to invest his $ 4,000 in a savings account with a real interest rate of 5% per year.

4 0

2 years ago

What are the steps to solving this equation <br><br>7x+3= 9x-3-2x

Luba_88 [7]

Simplify:

7x+3=7x-3

Now 7x goes away and you get 3=-3, which cannot be true, so there is no solution

7 0

2 years ago

Look at the formula for finding the volume of a rectangular prism below.

krek1111 [17]

V = LWH.....to find W, divide both sides by LH
V / LH = W <===

3 0

2 years ago

Every number other than 0 has a multiplicative inverse.

Gala2k [10]

Answer:

A multiplicative inverse of a real number x is a real number y such that xy = 1. ... ((NOT GOOGLING DEF))

Step-by-step explanation:

"For every real number x, if x 0, then there is a real number y such that xy = 1.”

3 0

2 years ago