Can someone please explain how to do this? You don't have to answer the questions but If you can give me an explanation/formula to solve. it would help me a lot thank you. marking brainliest when I can.

Answer:

B. 0.024

The p-value of the test is 0.024 < 0.05(standard significance level), which means that there is enough evidence that the proportion of freshmen who graduated in the bottom third of their high school class in 2001 has been reduced.

Step-by-step explanation:

Before testing the hypothesis, we need to understand the central limit theorem and subtraction of normal variables.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]

Subtraction between normal variables:

When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.

1999:

Of 100, 20 were in the bottom thid. So

[tex]p_B = \frac{20}{100} = 0.2[/tex]

[tex]s_B = \sqrt{\frac{0.2*0.8}{100}} = 0.04[/tex]

2001:

Of 100, 10 were in the bottom third, so:

[tex]p_A = \frac{10}{100} = 0.1[/tex]

[tex]s_A = \sqrt{\frac{0.1*0.9}{100}} = 0.03[/tex]

To determine this, you test the hypotheses H0 : p1 = p2 , Ha : p1 > p2.

Can also be rewritten as:

[tex]H_0: p_B - p_A = 0[/tex]

[tex]H_1: p_B - p_A > 0[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{s}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, and s is the standard error.

0 is tested at the null hypothesis:

This means that [tex]\mu = 0[/tex]

From the sample:

[tex]X = p_B - p_A = 0.2 - 0.1 = 0.1[/tex]

[tex]s_A = \sqrt{s_A^2+s_B^2} = \sqrt{0.03^2+0.04^2} = 0.05[/tex]

Value of the test statistic:

[tex]z = \frac{X - \mu}{s}[/tex]

[tex]z = \frac{0.1 - 0}{0.05}[/tex]

[tex]z = 2[/tex]

P-value of the test and decision:

The p-value of the test is the probability of finding a difference of proportions of at least 0.1, which is 1 subtracted by the p-value of z = 2.

Looking at the z-table, z = 2 has a p-value of 0.976.

1 - 0.976 = 0.024, so the p-value is given by option B.

The p-value of the test is 0.024 < 0.05(standard significance level), which means that there is enough evidence that the proportion of freshmen who graduated in the bottom third of their high school class in 2001 has been reduced.

Answer:

Step-by-step explanation:

If K is square number, then exponents in number N are even.

Answer:

C

Step-by-step explanation:

In the equation y = -x - 4, the gradient is -1.

While in the second equation,

5x + 5y = 20

y = -x + 4

So the gradient is -1 too

Both sides are not perpendicular to each other because if you apply the formula, m1m2 = -1, and if substitute both gradient, (-1)(-1) = 1 ≠ -1

Therefore, no they are not perpendicular but parallel instead.

Answer: C

Step-by-step explanation:

Look above fool

answer:

is this cool? or explanation?

Answer:

[tex]\frac{1}{x^{5} }[/tex]

Step-by-step explanation:

x^-12/ x^-7

= x^(-12-(-7))

= x^-5

= 1/x^5

Answer:

tan Z = 4/3

Step-by-step explanation:

Since this is a right triangle, we can use trig functions

tan theta= opp / adj

tan Z = 32/24

Divide top and bottom by 8

tan Z = 4/3

Answer:

10 packs of dvds

Step-by-step explanation:

$180 / $18 = 10 packs

You can buy a maximum of 10 dvd packs

Answer:

you can buy 10 dvds that is thr answer

Answer:

universal set is the right answer

4b² when b = -1/2

[tex] = {4( \frac{ - 1}{2})}^{2} \\ = 4( \frac{1}{4}) \\ = \frac{4}{4} \\ = 1[/tex]

Answer:

-4

Step-by-step explanation:

4b x 2 when b = -1/2

1) put -1/2 where b is.

4 x -1/2 x 2

2) solve.

-2 x 2

-4

Answer:

Step-by-step explanation:

4280 granos de maíz pira se requerirán para obtener una libra de palomitas de maíz.

Dado que algunos granos de maíz al ser calentados revientan y pierden agua de manera explosiva, y en promedio se puede considerar que tienen una masa de 125 mg y cuando explotan (palomitas de maíz) su masa es de 106 mg, para determinar cuántos granos de maíz pira se requerirán para obtener una libra de palomitas de maíz se debe realizar el siguiente cálculo:

Por lo tanto, 4280 granos de maíz pira se requerirán para obtener una libra de palomitas de maíz.

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Answer:

2, 0, 1

Step-by-step explanation:

In quadratic equations if b^2-4ac is greater than 0, 2 solutions. if equal, 1, if less, 0.

Answer:

the number A(t) of grams of salt in the tank at a time is A(t)=150-110e-t/50

Answer:

C is the answer

Step-by-step explanation:

Quadratic equations have at most 2 solution, and linear equations only have 1 solution, and since y is equal to both of them, it can only have 1 or 2 solutions.

The correct answer is option D.  The system may have no, 1, or 2 solutions

A quadratic equation is a second-order polynomial equation in a single variable x , ax²+bx+c=0. with a ≠ 0 .

f(x) is a quadratic function and g(x) is linear function

y=f(x)

y=g(x)

Quadratic equations have at most 2 solution

linear equations only have 1 solution,

f(x)=g(x)=y

y is equal to both of them, it can only have 1 or 2 solutions.

A line and a parabola can intersect zero, one, or two times

Therefore, a linear and quadratic system can have zero, one, or two solutions

Hence, the correct answer is option D.  The system may have no, 1, or 2 solutions

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Answer:

16/25 or 64%

Step-by-step explanation:

In this problem we see that 64 out of the 100 students did better on the exams. So, to find the answer we must find the percentage form of 64 out of 100.

Step one:

what exactly is 64 out of 100? Well, in the math world when we see 'out of' we know that means 'divided by'. So, 64 out of 100 is 64/100.

Step two:

now we have to turn 64/100 into a percentage. We know that 1/100 is 1% so lets multiply 1 by 64. 64*1 = 64. This means that 64/100 = 64%.

I'm not 100% sure what form you need your answer in but if you need it in percentage for the answer is 64%. If you need your answer in a fraction form the answer would be 64/100 or 16/25 if we simplify the answer.

I hope this helps!!

Using trigonometric identities, it is found that the value of [tex]\cos{\theta}[/tex] is given by:

B. [tex]\cos{\theta} = \frac{\sqrt{17}}{6}[/tex]

It is given by the division of it's sine by it's cosine, that is:

[tex]\tan{\theta} = \frac{\sin{\theta}}{\cos{\theta}}[/tex]

In this problem, the equation given is:

[tex]\tan{\theta} = -\sqrt{\frac{19}{17}}[/tex]

That is:

[tex]\frac{\sin{\theta}}{\cos{\theta}} = -\sqrt{\frac{19}{17}}[/tex]

[tex]\sin{\theta} = -\sqrt{\frac{19}{17}}\cos{\theta}[/tex]

The following identity is applied:

[tex]\sin^2{\theta} + \cos^2{\theta} = 1[/tex]

Then:

[tex]\left(-\sqrt{\frac{19}{17}}\cos{\theta}\right)^2 + \cos^2{\theta} = 1[/tex]

[tex]\frac{36}{17}\cos^2{\theta} = 1[/tex]

[tex]\cos^2{\theta} = \frac{17}{36}[/tex]

[tex]\cos{\theta} = \frac{\sqrt{17}}{6}[/tex]

More can be learned about trigonometric identities at https://brainly.com/question/24496175

Answer:

Hi sorry I just wanted to ask is it B or D? positive or negative?

Step-by-step explanation:

edmentum is the worst

Answer:

Step-by-step explanation:

[tex]\frac{9}{11}=0 .818181....[/tex]

     __  

= 0.81

Answer:

Area = 13.5 cm^2

Step-by-step explanation:

When we know 2 sides and the included angle

the area is  =(½)ab sin C

where a and b are the side lengths and C is the angle between them

Area = 1/2 ( 13*7) sin 38

Area = 13.48477

Rounding to the nearest tenth

Area = 13.5 cm^2

Answer:

The equation of the perpendicular line (PR) to line PQ is; y = -0.5x - 1.5

Step-by-step explanation:

The line is perpendicular to line adjoined by points P(-3,0) and Q(0,6)

The slope of line PQ is;

Slope = change in y ÷ change in x = [tex]\frac{6 - 0}{0 -- 3}[/tex] = 2

The product of slopes of two perpendicular lines = -1

Hence the slope of line PR = -1 ÷ slope of line PQ = -1/2

Taking another point (x,y) and point P(-3,0) the equation of line PR is;

Slope = [tex]\frac{y - 0}{x - -3} = -\frac{1}{2}[/tex]

Cross-multiplying gives;

2y = -x - 3 , y = -x/2 - 3/2 , y = -0.5x - 1.5

Answer:

Anna is right in her meaning concerning on triangle solvability.

Step-by-step explanation:

The side [tex]c[/tex] represents the hypotenuse of a right triangle as [tex]C = 90^{\circ}[/tex] and is opposite to that angle. There are two ways to solve this triangle trigonometrically:

i) Law of Sine

[tex]\frac{a}{\sin A} = \frac{b}{\sin B} = \frac{c}{\sin C}[/tex] (1)

ii) Law of Cosine

[tex]c^{2} = a^{2} + b^{2} - 2\cdot a\cdot b \cdot \cos C[/tex] (2)

The Pythagorean Theorem is a particular case of the Law of Cosine for [tex]C = 90^{\circ}[/tex]

The triangle cannot be solved as there is an input missing, either another side or another angle. If [tex]C = 90^{\circ}[/tex], then (2) is reduced into this form:

[tex]c^{2} = a^{2}+b^{2}[/tex] (2b)

In this case we need to know the measure of either [tex]a[/tex] or [tex]b[/tex] to determine its counterpart and the values of the missing angles by (1). In nutshell, Anna is right.

Answer:

78.5

Step-by-step explanation:

πr²

= π×5²

= 25π

= 78.5

Answer:

Step-by-step explanation:

The law of cosine helps us to know the third side of a triangle when two sides of the triangle are already known the angle opposite to the third side is given. The distance between A and B is 85.6 yds.

The law of cosine helps us to know the third side of a triangle when two sides of the triangle are already known the angle opposite to the third side is given. It is given by the formula,

[tex]c =\sqrt{a^2 + b^2 -2ab\cdot Cos\theta}[/tex]

where

c is the third side of the triangle

a and b are the other two sides of the triangle,

and θ is the angle opposite to the third side, therefore, opposite to side c.

The three points A, B, and C will form a triangle. Therefore, using the law of cosine the measure of the third side AB can be written as,

[tex]AB =\sqrt{(AC)^2 + (BC)^2 -2(AC)(BC)\cdot \cos(51.2^o)}\\\\AB =\sqrt{(80)^2 + (104)^2 -2(80)(104)\cdot \cos(51.2^o)}\\\\AB = \sqrt{6400+10816-16640\cos51.2^o}\\\\AB = \sqrt{7328.4}\\\\AB=85.6\rm\ yd[/tex]

Hence, the distance between A and B is 85.6 yds.

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Answer:

a. 5 hours

b. 40 kph

Step-by-step explanation:

300 km ÷ 60 km = 5 hours

200 km ÷ 5 hours = 40 kilometers per hour

Answer:

The 1st solution

Step-by-step explanation:

all of the values are satisfied.

Answer:

4000

Step-by-step explanation:

1 ton = 2000 pounds

2 tons = ? pounds

Multiply:

2000 × 2 = 4000

There will be 4000 pounds of crushed stone.

Hope this helped.

Sam ordered 2 tons of crushed stone. How many pounds of crushed stone does she have?

Here, we need to convert the tons into pounds to get the desired result

✪ According to the question :

We know that,

1 ton = 2000 pounds

2 tons = 2(1000 pounds) = 2000 pounds

Answer:

WX=10; VW=22; WY=20; VX=32; WZ=30;VY=42

Step-by-step explanation:

1)WX=XY=XZ/2=20/2=10

2)VW=VZ-WX-XY-YZ=VZ-3*WX=52-3*10=52-30=22

3)WY=WX+XY=2*WX=2*10=20

4)VX=VW+WX=22+10=32

5)WZ=WX+XY+YZ=3*WX=3*10=30

6)VY=VZ-YZ=52-10=42

The points V, W, X, Y and Z are collinear. The indicated lengths are

[tex]WX=10\\VW=22\\WY=20\\VX=32\\WZ=30\\VY=42[/tex]

Given :

points V, W, X, Y and Z are collinear, VZ= 52, XZ =20, and WX=XY=YZ

Lets make diagram using the given information

The diagram is attached below

XY=YZ

XZ=20, so [tex]XY+YZ=20\\Both XY and YZ are same\\XY+XY=20\\2XY=20\\Divide \; by \; 2\\XY=10[/tex]

[tex]WX=XY=YZ \\XY=10\\WY=10\\YZ=10\\[/tex]

Now we find out VW

[tex]VW+WX+XY+YZ=52\\VW+10+10+10=52\\VW+30=52\\Subtract \; 30\\VW=52-30\\VW=22[/tex]

Now we find the indicated length

[tex]WX =10[/tex]

[tex]VW=22\\WY=WX+XY=10+10=20\\VX=VW+WX=22+10=32\\WZ=WX+XY+YZ=10+10+10=30\\VY=VW+WX+XY=22+10+10=42[/tex]

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Answer:

The third exterior angle is [tex]103^o[/tex]

Step-by-step explanation:

Given

[tex]\theta = 158^o[/tex]

[tex]\alpha = 99^o[/tex]

Required

The third exterior angle [tex](\beta)[/tex]

The exterior angles of a triangle add up to 360 degrees.

So:

[tex]\theta + \alpha + \beta = 360^o[/tex]

Make [tex]\beta[/tex] the subject

[tex]\beta = 360^o - (\theta + \alpha)[/tex]

Substitute known values

[tex]\beta = 360^o - (158^o + 99^o)[/tex]

[tex]\beta = 103^o[/tex]

Answer:

-3.662rad × 180/π = -209.8°

Step-by-step explanation:

Answer:

1 degree = .01745329 radians

1 radian = 57.2957877856 degrees

-209.8 degrees = .01745329 * -209.8 =

-3.66170024200 radians

Step-by-step explanation:

Answer: 12

Step-by-step explanation:

16 X 20c = 3.20

12 x 5c = 0.60

total is 3.80

Amy has 12 five c coins.

Answer:

3

Step-by-step explanation: