I need help EXTRA POINTS!!

The poll found that 38% of a random sample of 1012 American adults said they believe in ghosts. What is the lower bound for a 90

Brrunno [24]

Answer:

The lower bound for a 90% confidence interval for the percentage of all American adults who believe in ghosts is 0.3549

Step-by-step explanation:

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:

$n = 1012, \pi = 0.38$

90% confidence level

So $\alpha = 0.1$ , z is the value of Z that has a pvalue of $1 - \frac{0.1}{2} = 0.95$ , so $Z = 1.645$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.38 - 1.645\sqrt{\frac{0.38*0.62}{1012}} = 0.3549$

The lower bound for a 90% confidence interval for the percentage of all American adults who believe in ghosts is 0.3549

6 0

4 years ago

Which graph matches the equation 3x -4y= 4

zloy xaker [14]

There is no graph to choose from, but the one you are looking for should look like the attached photo.

Hope this helps! Please make me the brainliest, it’s not necessary but appreciated, I put a lot of effort and research into my answers. Have a good day, stay safe and stay healthy.

4 0

3 years ago

A simple random sample of size nequals81 is obtained from a population with mu equals 83 and sigma equals 27. (a) Describe the

Ivanshal [37]

Answer:

a) $\bar X \sim N (\mu, \frac{\sigma}{\sqrt{n}})$

With:

$\mu_{\bar X}= 83$

$\sigma_{\bar X}=\frac{27}{\sqrt{81}}= 3$

b) $z= \frac{89-83}{\frac{27}{\sqrt{81}}}= 2$

$P(Z>2) = 1-P(Z$

c) $z= \frac{75.65-83}{\frac{27}{\sqrt{81}}}= -2.45$

$P(Z$

d) $z= \frac{89.3-83}{\frac{27}{\sqrt{81}}}= 2.1$

$z= \frac{79.4-83}{\frac{27}{\sqrt{81}}}= -1.2$

$P(-1.2$

Step-by-step explanation:

For this case we know the following propoertis for the random variable X

$\mu = 83, \sigma = 27$

We select a sample size of n = 81

Part a

Since the sample size is large enough we can use the central limit distribution and the distribution for the sampel mean on this case would be:

$\bar X \sim N (\mu, \frac{\sigma}{\sqrt{n}})$

With:

$\mu_{\bar X}= 83$

$\sigma_{\bar X}=\frac{27}{\sqrt{81}}= 3$

Part b

We want this probability:

$P(\bar X>89)$

We can use the z score formula given by:

$z = \frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}$

And if we find the z score for 89 we got:

$z= \frac{89-83}{\frac{27}{\sqrt{81}}}= 2$

$P(Z>2) = 1-P(Z$

Part c

$P(\bar X$

We can use the z score formula given by:

$z = \frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}$

And if we find the z score for 75.65 we got:

$z= \frac{75.65-83}{\frac{27}{\sqrt{81}}}= -2.45$

$P(Z$

Part d

We want this probability:

$P(79.4 < \bar X < 89.3)$

We find the z scores:

$z= \frac{89.3-83}{\frac{27}{\sqrt{81}}}= 2.1$

$z= \frac{79.4-83}{\frac{27}{\sqrt{81}}}= -1.2$

$P(-1.2$

8 0

4 years ago

Use synthetic division to solve (4x^3-3x^2+5x+6)/(x+6).what is the quotient

ladessa [460]

Answer:

The quotient= $4x^2-27x+167$ .

Step-by-step explanation:

Given

Dividened= $4x^3-3x^2+5x+6$

Divisor= $x+6$

In synthetic division : Put denomerator is equal to zero.

Put x+6=0

x=-6

Put -6 in division box as a divisor.

Coefficient of x^3=4

Coefficient of x^2=-3

Coefficient of x=5

Constant value=6

Put the coefficient of x^3,x^2,x and constant in descending order of power of x in division problem.

Now ,bring the coefficient of x^3 is 4 straight down .

Now, multiply the numbe -6 in the division box with the number 4 brought down and put the result -24 below the number - 3 of next column.

By adding we get -27 and write result in the bottom of row .

Again ,the number -6 multiply with -27 and put the result=162 below the number of next column.

By adding two number together we get 167 and put the result in the bottom of row.

Again, the number -6 in division box multiply with the number 167 and put the result=1002 below the number of next column.

Adding two number together we get 1008 and write in the bottom of row.

Last number is remainder and then write the remainder in fraction .

In quotient the power of x reduces by 1 from the numertor.

Hence, the quotient = $4x^2-27x+167$

Remainder= $\frac{1008}{x+6}$ .

7 0

3 years ago

Read 2 more answers

What is the surface area of the rectangular pyramid?

marin [14]

Answer:

181.044m²

Step-by-step explanation:

First, work of the surface area of the base (bottom rectangle area)

Formula : base × height

6×2=12m²

Formula : LW+L

For the 8.8 bit i got 83.734 (sorry i can't be asked right now to put down all my working out)

and for the 9 i got 85.31

add them all together we get 181.044

7 0

3 years ago

Read 2 more answers