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3 years ago

Which is an example of the associative property?

Mathematics

1 answer:

labwork [276]3 years ago

8 0

Answer:

C. is the associative property of addition.

Step-by-step explanation:

The associative property of addition is the fact that not matter how they are grouped, numbers added together still create the same sum. You'll see that in this example, they group different pairs, but you'd still get the same answer.

You might be interested in

Which expression equals 93102

Karo-lina-s [1.5K]

Answer:

you got this

Step-by-step explanation:

goodluck

4 0

2 years ago

Las edades de dos hermanos tienen una razón de 2 a 1. Cuando transcurran 4 años, la razón entre sus edades será de 8 a 6. ¿Cuánt

Nataly [62]

Answer:

The age of brothers are 4 years and 2 years respectively.

Step-by-step explanation:

We are given that the ages of two brothers have a ratio of 2 to 1. When 4 years have passed, the ratio of their ages will be 8 to 6.

Let the age of the first brother be 'x years' and the age of the second brother be 'y years'.

So, according to the question;

The first condition states that the ages of two brothers have a ratio of 2 to 1, that means;

$\frac{x}{y} =\frac{2}{1}$

$x=2y$ -------------- [equation 1]

The second condition states that when 4 years have passed, the ratio of their ages will be 8 to 6, that means;

$\frac{x+4}{y+4}=\frac{8}{6}$

$6({x+4})=8}(y+4)$

$6x+24=8y+32$

$6(2y)+24=8y+32$

$12y-8y=32-24$

$4y=8$

$y=\frac{8}{4}$ = 2 years

Putting the value of y in equation 1 we get;

x = 2y

x = $2 \times 2$ = 4 years

Hence, the age of brothers are 4 years and 2 years respectively.

3 0

2 years ago

1. Bailey withdrew $135 from her checking account. Write an algebraic expression that describes Bailey's action.

MArishka [77]

Answer:

c − 135

Explanation:

Let's say that the amount of money in Bailey's checking account is

c dollars.

We also know that she took away $ 135

From this variable and number, we can state the algebraic expression

c − 135

<h2>Hope this helps!</h2>

7 0

2 years ago

A woman is randomly selected from the 18–24 age group. For women of this group, systolic blood pressures (in mm Hg) are normally

Naddik [55]

Answer:

$X \sim N(114.8,13.1)$

Where $\mu=114.8$ and $\sigma=13.1$

We are interested on this probability

$P(X>140)$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

And we can find this probability using the complement rule:

$P(z>1.924)=1-P(z$

Step-by-step explanation:

Previous concepts

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 Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Solution to the problem

Let X the random variable that represent the variable of interest of a population, and for this case we know the distribution for X is given by:

$X \sim N(114.8,13.1)$

Where $\mu=114.8$ and $\sigma=13.1$

We are interested on this probability

$P(X>140)$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this: $P(X>140)=P(\frac{X-\mu}{\sigma}>\frac{140-\mu}{\sigma})=P(Z>\frac{140- 1114.8}{2.6})=P(z>1.924)$ And we can find this probability using the complement rule:

$P(z>1.924)=1-P(z$

8 0

3 years ago

Solve the system by using a matrix equation. --4x - 5y = -5 -6x - 8y = -2

evablogger [386]

Answer:

Solution : (15, - 11)

Step-by-step explanation:

We want to solve this problem using a matrix, so it would be wise to apply Gaussian elimination. Doing so we can start by writing out the matrix of the coefficients, and the solutions ( - 5 and - 2 ) --- ( 1 )

$\begin{bmatrix}-4&-5&|&-5\\ -6&-8&|&-2\end{bmatrix}$

Now let's begin by canceling the leading coefficient in each row, reaching row echelon form, as we desire --- ( 2 )

Row Echelon Form :

$\begin{pmatrix}1\:&\:\cdots \:&\:b\:\\ 0\:&\ddots \:&\:\vdots \\ 0\:&\:0\:&\:1\end{pmatrix}$

Step # 1 : Swap the first and second matrix rows,

$\begin{pmatrix}-6&-8&-2\\ -4&-5&-5\end{pmatrix}$

Step # 2 : Cancel leading coefficient in row 2 through $R_2\:\leftarrow \:R_2-\frac{2}{3}\cdot \:R_1$ ,

$\begin{pmatrix}-6&-8&-2\\ 0&\frac{1}{3}&-\frac{11}{3}\end{pmatrix}$

Now we can continue canceling the leading coefficient in each row, and finally reach the following matrix.

$\begin{bmatrix}1&0&|&15\\ 0&1&|&-11\end{bmatrix}$

As you can see our solution is x = 15, y = - 11 or (15, - 11).

4 0

2 years ago