Why is 0.5 rational?

11. A set of weights includes a 5 lb bar and 8 pairs of weight plates. Each pair of plates weighs 10 lbs. If x

Marat540 [252]

X is amount of plates 10lbs and f(x) is the function

4 0

3 years ago

A soccer ball manufacturer wants to estimate the mean circumference of soccer balls within 0.1 in. Determine the minimum sample

leva [86]

Answer:

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

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 $z_{\alpha/2}=1.96$ , replacing into formula (2) we got:

$n=(\frac{1.96(0.25)}{0.1})^2 =24.01$

So the answer for this case would be n=25 rounded up to the nearest integer

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".

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

$\mu$ population mean (variable of interest)

$\sigma=0.25$ represent the population standard deviation

n represent the sample size (variable of interest)

Solution to the problem

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

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

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 =0.1 and we are interested in order to find the value of n, if we solve n from equation (1) we got:

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

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 $z_{\alpha/2}=1.96$ , replacing into formula (2) we got:

$n=(\frac{1.96(0.25)}{0.1})^2 =24.01$

So the answer for this case would be n=25 rounded up to the nearest integer

8 0

4 years ago

How to write this numbers in word 30.659

Karo-lina-s [1.5K]

Answer:

thirty and six hundred fifty-nine thousandths

Step-by-step explanation:

6 0

3 years ago

36 + m = 54 54 - 36 = m 36 + 54 = m 54 / 36 = m 36 x 54 = m

luda_lava [24]

Answer:

me and you have the same last name.

Step-by-step explanation:

thats cool

3 0

4 years ago

65% of what number is 39 then write an equation

Volgvan

Answer:

60

Step-by-step explanation:

65% = .65, so

60 × .65 = 39

or the equation could be

60/.65 = x

Hope this helps, if not please let me know and i will do my best to correct my mistake.

6 0

3 years ago