If rectangle ABCD is resized with a central point (−1, 1) and scale factor 3, what are the coordinates of D'?

How many pounds must a sand bag weigh to test if a safety net can absorb the proper amount of force?

Agata [3.3K]

its 400lbs
hope i helped

4 0

4 years ago

A random sample of the correct choice on 400 multiple-choice questions on a variety of AP exams1 shows that B was the most commo

maks197457 [2]

Answer:

a) Null hypothesis: $p\leq 0.2$

Alternative hypothesis: $p > 0.2$

b) $z=\frac{0.225 -0.2}{\sqrt{\frac{0.2(1-0.2)}{400}}}=1.25$

$p_v =P(Z>1.25)=0.106$

Step-by-step explanation:

1) Data given and notation

n=400 represent the random sample taken

X=90 represent the number of questions with B as the correct answer

$\hat p=\frac{90}{400}=0.225$ estimated proportion of arrests that were not prosecuted

$p_o=0.2$ is the value that we want to test, since we assume that each question present 5 options and just one is correct, 1/5 =0.2 if all five options were equally likely

$\alpha$ represent the significance level

z would represent the statistic (variable of interest)

$p_v$ represent the p value (variable of interest)

2) Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the true proportion is higher than 0.2.:

Null hypothesis: $p\leq 0.2$

Alternative hypothesis: $p > 0.2$

When we conduct a proportion test we need to use the z statisitc, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

3) Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.225 -0.2}{\sqrt{\frac{0.2(1-0.2)}{400}}}=1.25$

4) Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The significance level provided $\alpha$ . The next step would be calculate the p value for this test.

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

$p_v =P(Z>1.25)=0.106$

If we compare the p value obtained and the significance level assumed $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL reject the null hypothesis, and we can said that at 5% of significance the proportion of B correct answers is not significantly higher than 0.2.

8 0

4 years ago

The amount that Ronnie earns, E, in terms of the number of hours that he works, h, is shown in

cestrela7 [59]

Answer:

8

Step-by-step explanation:

The constant of proportionality bus the amount earned by Ronnie, E, all over the corresponding hours he used in working, h.

Constant of proportionality = $\frac{E}{h}$

From the graph given, when h = 5, E = 40.

Therefore:

Constant of proportionality = $\frac{E}{h} = \frac{40}{5} = 8$

4 0

3 years ago

Help please :(. :( :(.,,,,,,,,,,,,,,,,

Volgvan

Answer:

y-intercept: y=9
zeros: x= -3, -1, 1, 3

Step-by-step explanation:

The y-intercept is where the graph crosses the y-axis. On this graph, that is just below y=10. A reasonable estimate* of the y-intercept is y=9.

__

The zeros are those places on the graph where y=0. The line y=0 is the x-axis, so the zeros are the x-values of the places where the graph crosses the x-axis. Those points are clearly labeled: x = -3, -1, 1, 3.

_____

* Knowing the zeros, you can write a factored-form equation for the graph:

y = (x +3)(x +1)(x -1)(x -3)

You can substitute x=0 in this equation to see what the y-intercept would be:

3×1×-1×-3 = 9

That is, with no scale factor applied to the function, its y-intercept would be 9. This is the same value we estimated above, so it is reasonable to assume that value is correct.

8 0

4 years ago

1. What effect does the scaling have on the volume? (of a ice cream cone)

sergij07 [2.7K]

Enlarging the radius of the ice cream cone will result in a volume that is larger by twice the amount of the scale on the radius. For instance, doubling the radius will make the volume 4 times larger.
Enlarging the height of the ice cream cone will result in a volume that is larger by the same amount as the scale on the height. For instance, doubling the height will make the volume 2 times larger.
Going from these answers, the price will change in the same manner as the volume changes. A doubled volume would be a doubled price; a volume 4 times as large will result in a price 4 times as much.

The volume of a cone is given by the formula

V=(1/3)πr²h

If we double the radius, we then have

V=(1/3)π(2r)²h = (1/3)π(4r²)h = 4(1/3)πr²h.

Doubling the height instead will give us:

V=(1/3)πr²(2h) = 2(1/3)πr²h

8 0

4 years ago