Using the z-distribution, as we are working with a proportion, it is found that the 99% confidence interval for the proportion of all U. S. Adults who would include the 9/11 attacks on their list of 10 historic events is (0.7458, 0.7942). It means that we are 99% sure that the true proportion for all U.S. adults is between these two bounds.

<h3>What is a confidence interval of proportions?</h3>

A confidence interval of proportions is given by:

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

In which:

$\pi$ is the sample proportion.

z is the critical value.

n is the sample size.

In this problem, the parameters are:

$z = 2.575, n = 2000, \pi = 0.77$

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.77 - 2.575\sqrt{\frac{0.77(0.23)}{2000}} = 0.7458$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.77 + 2.575\sqrt{\frac{0.77(0.23)}{2000}} = 0.7942$

The 99% confidence interval for the proportion of all U. S. Adults who would include the 9/11 attacks on their list of 10 historic events is (0.7458, 0.7942). It means that we are 99% sure that the true proportion for all U.S. adults is between these two bounds.

More can be learned about the z-distribution at brainly.com/question/25890103

7 0

2 years ago

Drag each expression to show whether it is equivalent to 36x + 9, 9(4x – 1), or (4 • 9x) + (4 • 2).

lora16 [44]

In order to find out what 36x + 9 is equivalent to,, we must factor out 9 from the expression. Once we do this you will find that this expression is equivalent to 9(4x + 1),, or option E.
Next we will look at the expression 9(4x -1). In order for us to find out the equivalent to this expression,, we must first multiply each term in the parenthesis by 9.
9 × 4x - 9
Now calculate the product
36x - 9
This means that the equivalent for this expression is 36x - 9,, or option A.
Lastly,, we will look at the final expression given which is 4(9x + 2). The first step for finding the equivalent of this expression is to multiply the numbers in the first parenthesis together.
(36x) + (4 × 2)
Now multiply the numbers in the second parenthesis together.
(36x) + 8
Remove the parenthesis
36x + 8
Now factor out 4 from the expression to get your final answer.
4(9x + 2)
This means that the last expression is equivalent to 4(9x + 2),, or option C.
Let me know if you have any further questions
:)

3 0

3 years ago

Now round 3.152 to the nearest one.

Alika [10]

3

Mark brainliest please

Hope this helps you

8 0

2 years ago