Explain how to use the combine place values strategy to find 223-19.

A union of restaurant and foodservice workers would like to estimate the mean hourly wage, μ, of foodservice workers in the U.S.

pav-90 [236]

Answer:

$n=(\frac{1.960(2.25)}{0.35})^2 =158.76 \approx 159$

So the answer for this case would be n=159 rounded up to the nearest integer

Step-by-step explanation:

Assuming this complete question: A union of restaurant and foodservice workers would like to estimate the mean hourly wage, , of foodservice workers in the U.S. The union will choose a random sample of wages and then estimate using the mean of the sample. What is the minimum sample size needed in order for the union to be 95% confident that its estimate is within $0.35 of ? Suppose that the standard deviation of wages of foodservice workers in the U.S. is about $2.15 .

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

$\sigma=2.25$ represent the population standard deviation

n represent the sample size

Solution to the problem

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{s}{\sqrt{n}}$ (a)

And on this case we have that ME =0.35 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=(\frac{z_{\alpha/2} \sigma}{ME})^2$ (b)

The critical value for 95% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.025;0;1)", and we got $z_{\alpha/2}=1.960$ , replacing into formula (b) we got:

$n=(\frac{1.960(2.25)}{0.35})^2 =158.76 \approx 159$

So the answer for this case would be n=159 rounded up to the nearest integer

3 0

3 years ago

Which number is the decimal form of ? 03 0.36 2.7 0.375

solniwko [45]

Answer:

0.36

Step-by-step explanation:

because it is the answer

6 0

3 years ago

In order for Brady to earn a B in his biology course, is this Christmas every day at least 80%. On the first artist, he has an a

Zepler [3.9K]

Im sorry !! but can you pleasee help me with my last question i just posted i really need help!!!! :(

8 0

3 years ago

Lucinda wants to build a square sandbox but has no way of measuring angles. Explain how she can make sure that the samdbox is me

amm1812

Option B. Arrange four-length sides so the diagonals are equal in length. Since a square is a rectangle with four equal sides the diagonals should bisect each other at each length and at 90 degrees to each other. This is really important. If the diagonals are equal in length and bisect each other at equal distance then the sandbox is measuring length and has equal angles which is a square by definition

8 0

3 years ago

Hisako sells dolls at her doll store. If she sells a doll for $33, and there is 4% sales tax, what is the total cost of the doll

Keith_Richards [23]

Find the total price

original price × sales tax

33 × 0.04 = 1.32

Add original price & sales tax

33 + 1.32 = 34.32

Hisako will pay $34.32 for her doll.

4 0

4 years ago