All categories

2 years ago

Identify the property used in each step of solving the inequality 3x – 2 > –4.

Mathematics

2 answers:

cestrela7 [59]2 years ago

8 0

Answer:

Addition Property and Multiplication Property

Step-by-step explanation:

Marizza181 [45]2 years ago

7 0

Answer:addition and multiplication

Step-by-step explanation:

I just did it

You might be interested in

It is believed that as many as 23% of adults over 50 never graduated from high school. We wish to see if this percentage is the

JulijaS [17]

Answer:

1) n=48

2) n=298

3) n=426

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".

$p$ represent the real population proportion of interest

$\hat p$ represent the estimated proportion for the sample

n is the sample size required (variable of interest)

$z$ represent the critical value for the margin of error

The population proportion have the following distribution

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

Part 1

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 90% of confidence, our significance level would be given by $\alpha=1-0.90=0.10$ and $\alpha/2 =0.05$ . And the critical value would be given by:

$z_{\alpha/2}=-1.64, z_{1-\alpha/2}=1.64$

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 $ME =\pm 0.1$ 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)

We can assume that the estimated proportion is 0.23 for the 25 to 30 group. And replacing into equation (b) the values from part a we got:

$n=\frac{0.23(1-0.23)}{(\frac{0.1}{1.64})^2}=47.63$

And rounded up we have that n=48

Part 2

The margin of error on this case changes to 0.04 so if we use the same formula but changing the value for ME we got:

$n=\frac{0.23(1-0.23)}{(\frac{0.04}{1.64})^2}=297.7$

And rounded up we have that n=298

Part 3

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 $ME =\pm 0.04$ 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)

We can assume that the estimated proportion is 0.23 for the 25 to 30 group. And replacing into equation (b) the values from part a we got:

$n=\frac{0.23(1-0.23)}{(\frac{0.04}{1.96})^2}=425.22$

And rounded up we have that n=426

3 0

2 years ago

Leonel runs on different trails near his home for exercise. uses of positioning device to record how far from home he is when he

anygoal [31]

Answer:

Step-by-step explanation:

bipb asfjsdhjkdshfjsdkhjfjhkdfssjfdjdfjkdfjdfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffsssssssssssssssssssefffffffffffffffllllllllllllllllllllllllllllllllllllllllllll mmmmmmmm;fsaeeeeeeeeeeeeeeeeeeeeeeeeeeeejragk b;;;;;;;;;;;;;;;;;;;jr bgakgbrrrrrrrradjl abrgjll abgrkakgbjrkbagjr gbjrjlkfda v .vvvvvvvvvvvvvvvvvvvf

3 0

1 year ago

What is the period of the function f(x) shown in the graph?

MariettaO [177]

Answer:

(0,-2)

Step-by-step explanation:

4 0

1 year ago

Read 2 more answers

Find a matrix representation of the transformation L(x, y) = (3x + 4y, x − 2y).

mario62 [17]

Answer:

$\left[\begin{array}{cc}x&y\end{array}\right] * \left[\begin{array}{cc}3&1\\4&-2\end{array}\right] = \left[\begin{array}{cc}3x+4y&x-2y\end{array}\right]$

Step-by-step explanation:

The general matrix representation for this transformation would be:

$\left[\begin{array}{cc}x&y\end{array}\right] * A = \left[\begin{array}{cc}3x+4y&x-2y\end{array}\right]$

As the matrix A should have the same amount of rows as columns in the firs matrix and the same amount of columns as the result matrix it should be a 2x2 matrix.

$\left[\begin{array}{cc}x&y\end{array}\right] * \left[\begin{array}{cc}a&b\\c&d\end{array}\right] = \left[\begin{array}{cc}3x+4y&x-2y\end{array}\right]$

Solving the matrix product you have that the members of the result matrix are:

3x+4y = a*x + c*y

x - 2y = b*x + d*y

So the matrix A should be:

$\left[\begin{array}{cc}3&1\\4&-2\end{array}\right]$

8 0

2 years ago

Marissa ate six slices of pizza from the 16-piece large pizza. What percent of the pizza did she eat?

olya-2409 [2.1K]

Answer:

0.96%

Step-by-step explanation:

look on google and search dollar times it helps with problems like this

hope this helps

7 0

2 years ago