Use the properties of real numbers to rewrite the expression. 2/5 * (-7) * 5/2

A segment with endpoint M Left parenthesis 5 comma 9 right parenthesis and N Left parenthesis 4 comma 3 right parenthesis is rot

mario62 [17]

Refer to the diagram below

If we draw a line that connects the center of rotation to one of the points, say point N, and take this line as the 0° position, then we need three 'turn' of 90° to get to 270°.

Coordinate of N' (-3, 4)
Coordinate of M' (-9, 5)

3 0

3 years ago

Translation: 4 units left and 4 units up<br> J(−1, −2), A(−1, 0), N(3, −3)

Molodets [167]

Answer:

(-5,2), (-5,4), and (-1,1)

Step-by-step explanation:

3 0

3 years ago

Cory, Josh and Dan went shopping for Halloween treats. Cory bought 3 chocolate pumpkins, 4 masks and 8 candy witches. He spent $

bija089 [108]

Answer:

The cost of chocolate pumpkins is $1.89, masks cost $5.75 and candy witches cost $1.62

Step-by-step explanation:

Let x represent the cost of chocolate pumpkins, y the cost of masks and z the cost of candy witches.

Cory shopping can be represented as:

3x + 4y + 8z = 41.63 (1)

Josh shopping can be represented as:

6x + 2y + 14z = 45.52 (2)

Dan shopping can be represented as:

8x + 3y + 25z = 72.87 (3)

The equations in matrix form is:

$\left[\begin{array}{ccc}3&4&8\\6&2&14\\8&3&25\end{array}\right] \left[\begin{array}{c}x\\y\\z\end{array}\right] =\left[\begin{array}{c}41.63\\45.52\\72.87\end{array}\right] \\\\\\\left[\begin{array}{c}x\\y\\z\end{array}\right] =\left[\begin{array}{ccc}3&4&8\\6&2&14\\8&3&25\end{array}\right] ^{-1}\left[\begin{array}{c}41.63\\45.52\\72.87\end{array}\right] \\\\\\\left[\begin{array}{c}x\\y\\z\end{array}\right] =\left[\begin{array}{c}1.89\\5.75\\1.62\end{array}\right]$

The cost of chocolate pumpkins is $1.89, masks cost $5.75 and candy witches cost $1.62

7 0

3 years ago

Please help with this question.

Ann [662]

Answer:

I believe the answer is B

Step-by-step explanation:

PLZ MARK BRAINLIEST

3 0

3 years ago

Read 2 more answers

2.06. In a study to estimate the proportion of residents in a certain city and its suburbs who favor the construction of a nucle

DaniilM [7]

Answer:

$z=\frac{0.74-0.56}{\sqrt{0.64(1-0.64)(\frac{1}{100}+\frac{1}{125})}}=2.795$

$p_v =2*P(Z>2.795)= 0.005$

So if we compare the p value and using any significance level for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can conclude that the proportions are different at 5% of significance.

Step-by-step explanation:

Data given and notation

$X_{1}=74$ represent the number of residents in a certain city and its suburbs who favor the construction of a nuclear power plant

$X_{2}=70$ represent the number of people suburban residents are in favor

$n_{1}=100$ sample 1 selected

$n_{2}=125$ sample 2 selected

$p_{1}=\frac{74}{100}=0.74$ represent the proportion of residents in a certain city and its suburbs who favor the construction of a nuclear power plant

$p_{2}=\frac{70}{125}=0.56$ represent the proportion of suburban residents are in favor

z would represent the statistic (variable of interest)

$p_v$ represent the value for the test (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the proportions are different, the system of hypothesis would be:

Null hypothesis: $p_{1} = p_{2}$

Alternative hypothesis: $p_{1} \neq p_{2}$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}$ (1)

Where $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{74+70}{100+125}=0.64$

Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.74-0.56}{\sqrt{0.64(1-0.64)(\frac{1}{100}+\frac{1}{125})}}=2.795$

Statistical decision

The significance level provided is $\alpha=0.05$ ,and we can calculate the p value for this test.

Since is a two tailed test the p value would be:

$p_v =2*P(Z>2.795)= 0.005$

So if we compare the p value and using any significance level for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can conclude that the proportions are different at 5% of significance.

5 0

3 years ago