Solve the equation 1/x + 1/3x =4

In a survey, the planning value for the population proportion is . How large a sample should be taken to provide a confidence in

tatuchka [14]

Answer:

n=350

Step-by-step explanation:

Notation and definitions

$n$ random sample taken (variable of interest)

$\hat p=0.35$ estimated proportion (value assumed)

$p$ true population proportion

Confidence =0.95 or 95% (value assumed)

Me=0.05 (value assumed)

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".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{\hat p(1-\hat p)}{n}})$

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by $\alpha=1-0.95=0.05$ and $\alpha/2 =0.025$ . And the critical value would be given by:

$z_{\alpha/2}=-1.96, z_{1-\alpha/2}=1.96$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.05$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

And replacing into equation (b) the values from part a we got:

$n=\frac{0.35(1-0.35)}{(\frac{0.05}{1.96})^2}=349.586$

And rounded up we have that n=350

4 0

3 years ago

I need help with number 16 please.

Kruka [31]

The graph is misleading because the sizes compared to the percentages are off. a more appropriate way to show the data would be with a bar graph.
Hope this helps!
Vote me brainliest!

8 0

3 years ago

The width of a rectangle is 4 1/6 feet, and its area is 35 square feet. What is the perimeter of this rectangle?

DanielleElmas [232]

Answer:

perimeter = 25.13feets

Step-by-step explanation:

width = 25/6 feet

Area = 35 square feet

lenght = Area/width = (35*6)/25 = 8.4feets

perimeter of the rectangle = 2(25/6 + 8.4) = 25.13 feets

5 0

3 years ago

Simplify this equation Thanks a lot!!!

den301095 [7]

Answer:

-1

Step-by-step explanation:

We need to simplify the given expression . The given expression is ,

$\rm\implies ( 2 \sqrt6 +5)^{2n-1} ( 2\sqrt6 - 5)^{2n-1}$

Here we can see that the power of the both exponent is same that is (2n+1) . Recall the property of exponents ,

$\bf\implies a^m \times b^m = (ab)^m$

Using this property , we have ,

$\rm\implies ( 2 \sqrt6 +5)^{2n-1} ( 2\sqrt6 - 5)^{2n-1}$

This can be written as ,

$\rm\implies\{( 2 \sqrt6 +5) ( 2\sqrt6 - 5)\}^{2n-1}$

Simplifying using ( a+b)(a-b) = a² - b² ,

$\rm\implies\{( 2 \sqrt6)^2 -5^2 \}^{2n-1}\\\\\rm\implies ( 24 - 25)^{2n-1}$

Subtracting the numbers inside the brackets ,

$\rm\implies (-1)^{2n - 1 }$

Now we know that every odd number is in the form of 2n -1 , where n is any integer. Therefore , the power is odd .

Since the base is (-1) , for even power it is 1 and for odd power it is -1 . Therefore the final answer is ,

$\rm\implies\boxed{\quad \red{ -1 }\quad }$

Hence the required answer is (-1) .

4 0

3 years ago

Why can you use Linear Pairs and Vertical Angles to prove lines are parallel?

natta225 [31]

Answer:

The reason why linear pairs and vertical angles are used to prove lines are parallel is because they area transversal drawn through the parallel lines will form angles on each of the two parallel lines including;

1) Supplementary linear pairs and

2) Vertical angles

3) Alternate angles

Given that either;

a) The corresponding angles that form the linear pairs are congruent

b) The corresponding vertically opposite angles are congruent

c) The corresponding alternate angles are congruent, we have;

The two lines are said to be parallel.

Step-by-step explanation:

5 0

3 years ago