What is .125 written as a percent

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

Krystal went To the carry out to purchase some items. She purchased four bottles of pop, three candy bars, and two bags of chips

Sunny_sXe [5.5K]

Answer:

Equation to determine crystals total bill (T) =(7.7+2x) - 1.50

Step-by-step explanation:

Given:

Number of bottles of pop purchased = 4

Number of candy bars purchased = 3

Number of chips bag purchased = 2

Cost of per bottle of pop = $1.25

Cost of per candy bar = $.90

Cost of the coupon = $1.50

To Find :

Equation to determine crystals total bill (T) given the cost of one bag of chips = ?

Solution:

Let the cost of one chips bag be x

Cost of 4 bottles of pop

=> $4 \times 1.25$

=>$ 5

Cost of 3 candy bars

=> $3 \times 0.90$

=>$ 2.7

Cost of 2 bags of chips

=> $2 \times x$

=>$ 2x

Now the total cost of the bill is

T = 5 + 2.7+ 2x

T =7.7+2x

Also Krystal had a coupon worth $1.50, the cost of the ticket will be

T =(7.7+2x) - 1.50

7 0

4 years ago

If f(x)=2x and g(x)=1/x, what is the domain of (fg)(x)

boyakko [2]

Answer is All real No.s

6 0

3 years ago

I need help ASAP please and thank you

Pavel [41]

9514 1404 393

Answer:

C. 4 +√(x+5)

Step-by-step explanation:

The sign between the terms changes to form the conjugate. The radical contents are unchanged.

The conjugate of 4 -√(x+5) is 4 +√(x+5).

_____

<em>Additional comment</em>

The utility of a conjugate is that the product of a number and its conjugate is the difference of two squares. The squares are intended to remove an undesirable feature of the number, its imaginary part or its irrational part, for example. Here, the product of the number and its conjugate would be ...

(a -b)(a +b) = a² -b²

4² -(√(x+5))² = 16 -(x +5) = 11 -x . . . . no longer contains a root

7 0

3 years ago

Parabola A can be represented using the equation (x + 3)2 = y, while line B can be represented using the equation y = mx + 9. Is

tekilochka [14]

Answer:

The correct answer is C

Step-by-step explanation:

Isabel is incorrect because the point of intersection between line B and parabola A that can be determined is the y-intercept of the equations

Hope this helps!

3 0

3 years ago

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