HELP!! ASAP!!

Researchers are interested if a school breakfast program leads to taller children. Assume that the population of all 5 year-old

DedPeter [7]

Answer:

$39-1.96\frac{1}{\sqrt{25}}=38.608$

$39+1.96\frac{1}{\sqrt{25}}=39.392$

So on this case the 95% confidence interval would be given by (38.608;39.392)

Step-by-step explanation:

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".

$\bar X=39$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

$\sigma=1$ represent the population standard deviation

n=25 represent the sample size

Solution to the problem

The confidence interval for the mean is given by the following formula:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

The margin of error is given by:

$ME= z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a tabel to find the critical value. The excel command would be: "=-NORM.INV(0.025,0,1)".And we see that $z_{\alpha/2}=1.96$

And replacing we got:

$ME= 1.96 *\frac{1}{\sqrt{25}}= 0.392$

Now we have everything in order to replace into formula (1):

$39-1.96\frac{1}{\sqrt{25}}=38.608$

$39+1.96\frac{1}{\sqrt{25}}=39.392$

So on this case the 95% confidence interval would be given by (38.608;39.392)

7 0

3 years ago

Which percent is equivalent to 7/20? a- 28% b- 7% c- 35% d- 27%

mash [69]

First change 7/20 into a decimal fraction: 35/100.

Then multiply this result by 100%: 35%

4 0

3 years ago

Help!!!!!!! can someone please give me the correct answer pleases

MArishka [77]

Answer:

It's 117 Degrees

5 0

3 years ago

WHEN adding integers and the signs are different, how do you know what the sign will be?

Neko [114]

Step-by-step explanation:

when you add integers remember that the positive integers move you to the right (so the integer will increase) and negative integers move you to the left (so the integer will decrease)

Hope this helps.

4 0

3 years ago

ANS FASTestttttttttttttttttttttttt

fenix001 [56]

Answer:

x is 75° ........................

5 0

2 years ago