Write each power as a product of the same factor. Then find the value. 7^2

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)

$\sigma=0.85$ represent the sample standard deviation

n represent the sample size (variable of interest)

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

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

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

And on this case we have that ME =0.25 and we are interested in order to find the value of n, if we solve n from equation (1) we got:

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

The critical value for 90% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.05,0,1)", and we got $z_{\alpha/2}=1.64$ , replacing into formula (2) we got:

$n=(\frac{1.64(0.85)}{0.25})^2 =31.09$

So the answer for this case would be n=32 rounded up to the nearest integer

5 0

4 years ago

Jamie says the value of 1.43 × (− 22 43 ) is close to −0.75. Student A says this estimate is reasonable because the product is n

enyata [817]

Answer:

Student A says this estimate is reasonable because… Get ... Student A says this estimate is reasonable because the product is negative and about half of 1.5. Student B says you could find the product using a calculator as follows: "Divide −18 by 35, multiply the quotient by 1.43, then round the product

Step-by-step explanation:

calculations with a calculator or computer we need a way of checking that the answers it ... introduce students to this way of thinking and give them practice at estimating simple ... Do they always get the right answer no matter what? Invent a story illustrating a calculator error that you may have made or use the following.

4 0

3 years ago