What is the answer for the #2 ASAP

. Compute the required sample size given the required confidence in the sample results is 99.74% (Z score of 3). The level of al

Shtirlitz [24]

Answer:

900 sample size

Step-by-step explanation:

To determine the sample size for a proportion, the margin of error formula is used to determine this:

$E=Z_{\frac{\alpha}{2} }*\sqrt{\frac{\hat p \hat q}{{n} }$

$n=\hat p \hat q*(\frac{Z_{\frac{\alpha}{2} }}{E} )^2$

Where p is the proportion, E is the margin of error, n is the sample size, q = 1 - p, $Z_\frac{\alpha }{2}$ is the z score.

Since the proportion is not known, the sample size needed to guarantee the confidence interval and error is at p = 0.5 and q = 1 - p = 1 - 0.5 = 0.5

E = 5% = 0.05, $Z_\frac{\alpha }{2}$ = 3. Hence:

$n=0.5*0.5*(\frac{3}{0.05} )^2\\\\n = 900$

6 0

3 years ago

Carson wants to construct a triangle with side lengths of 4 inches, 7 inches, and 12 inches. Which best describes a triangle wit

andrey2020 [161]

Answer: 2

Step-by-step explanation: Of course you probably never learned this

3 0

3 years ago

A class consists of 1/2 freshmen, 1/8 sophomores, and 1/8 juniors; the rest are seniors. What fraction of the class is seniors?

Firlakuza [10]

Answer:

2/8

Step-by-step explanation:

freshman=4/8

1/8 soph 1/8 jr

add all together u get 6/8

the rest is seniors so its 2/8

8 0

3 years ago

Please Help!

KonstantinChe [14]

Answer:

y = x^2 - 6 and y = x - 4

Step-by-step explanation:

It's x^2 - 6, because the parabola was moved 6 down, and positive slope, so in the linear, x is positive

7 0

2 years ago

Annual starting salaries for college graduates with degrees in business administration are generally expected to have a populati

valkas [14]

Answer:

A sample of 139 should be taken.

Step-by-step explanation:

We have that to find our $\alpha$ level, that is the subtraction of 1 by the confidence interval divided by 2. So:

$\alpha = \frac{1 - 0.95}{2} = 0.025$

Now, we have to find z in the Ztable as such z has a pvalue of $1 - \alpha$ .

That is z with a pvalue of $1 - 0.025 = 0.975$ , so Z = 1.96.

Now, find the margin of error M as such

$M = z\frac{\sigma}{\sqrt{n}}$

In which $\sigma$ is the standard deviation of the population and n is the size of the sample.

Population standard deviation of $3,000.

This means that $\sigma = 3000$

How large a sample should be taken if the desired margin of error is $500?

A sample of n is needed.

n is found when M = 500. So

$M = z\frac{\sigma}{\sqrt{n}}$

$500 = 1.96\frac{3000}{\sqrt{n}}$

$500\sqrt{n} = 1.96*3000$

Dividing both sides by 500

$\sqrt{n} = 1.96*6$

$(\sqrt{n})^2 = (1.96*6)^2$

$n = 138.3$

Rounding up:

A sample of 139 should be taken.

7 0

3 years ago