please help me please i will give brainliest

Answer:

A) (√3-√2)/(√3+√2)

Step-by-step explanation:

i think so

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:

The probability that you won't be a hobbit=

[tex] \frac{2}{3} [/tex]

The probability that you won't choose an umbrella=

[tex] \frac{4}{5} [/tex]

Step-by-step explanation:

The characters are 3, minus the hobbit gives you 2. So the probability of that=

[tex] \frac{2}{3} [/tex]

The weapons are 5, minus the umbrella is 4. So the probability of that=

[tex] \frac{4}{5} [/tex]

Answer:  A. 300 m

Work Shown:

L/100 = 15/5

5L = 100*15

5L = 1500

L = 1500/5

L = 300

Answer:

3

Step-by-step explanation:

5 1/3 ÷ 1 7/9

Change to improper fractions

5 1/3 = (3*5+1)/3 = 16/3

1 7/9 = (9*1+7)/9 = 16/9

16/3 ÷ 16/9

Copy dot flip

16/3 * 9/16

Rewriting

16/16 * 9/3

1*3

3

Answer:

A

Step-by-step explanation:

(f*g)(x) = f(x) * g(x)

=(x2+1)(x4-1)=x6-x2+x4-1

The two congruent base angles tell us that this triangle is isosceles, meaning it has two congruent sides. Therefore, we can set the two expressions equal to each other and solve from there.

9x - 73 = 3x + 23

6x - 73 = 23

6x = 96

x = 16

Side = 3(16) + 23 = 48 + 23 = 71

Hope this helps!

Answer:

x = 16

Step-by-step explanation:

Since the base angles are the same, the side lengths are the same

9x- 73 = 3x+23

Subtract 3x from each side

9x - 3x- 73 = 3x+23 -3x

6x- 73 = 23

Add 73 to each side

6x - 73 +73 = 23+73

6x = 96

Divide by 6

6x/6 = 96/6

x =16

Answer:

x = 46.9

Step-by-step explanation:

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

sin theta = opp / hyp

sin  54 = x / 58

58 sin 54 =x

x=46.92298

To the nearest tenth

x = 46.9

Answer:

x = 10

Step-by-step explanation:

7x - 15 = 4x + 15

7x - 4x = 15 + 15

3x = 30

x = 10

Answer:

x = 10

Step-by-step explanation:

Given that AC and BD are congruent , then

7x - 15 = 4x + 15 ( subtract 4x from both sides )

3x - 15 = 15 ( add 15 to both sides )

3x = 30 ( divide both sides by 3 )

x = 10

Answer: 75th term

Step-by-step explanation:

If you look at the first terms, you can see that we're subtracting 12 from the previous term to get the number. Knowing this, we can write an expression for the nth term. The expression would be -12n + 20. Since this specific term has value of -880, we set -880 equal to the value of -12n+20. By setting your equation like this -12n + 20 = -880 and solving, you get n = 75, which means the 75th term has a value of -880.

Answer:

45

Step-by-step explanation:

a44 = 2 + (43 × 1) = 2 + 43 = 45

Answer:

m(∠C) = 18°

Step-by-step explanation:

From the picture attached,

m(arc BD) = 20°

m(arc DE) = 104°

Measure of the angle between secant and the tangent drawn from a point outside the circle is half the difference of the measures of intercepted arcs.

m(∠C) = [tex]\frac{1}{2}[\text{arc(EA)}-\text{arc(BD)}][/tex]

Since, AB is a diameter,

m(arc BD) + m(arc DE) + m(arc EA) = 180°

20° + 104° + m(arc EA) = 180°

124° + m(arc EA) = 180°

m(arc EA) = 56°

Therefore, m(∠C) = [tex]\frac{1}{2}(56^{\circ}-20^{\circ})[/tex]

m(∠C) = 18°

Answer:

C. 36π units²

Step-by-step explanation:

Surface area of a sphere: 4πr²

[tex]4\pi r^2\\4\pi (3)^2\\4\pi (9)\\36\pi[/tex]

Answer:

Bruce's tiles covered more area than Felicia's, so this means Bruce has the greater unit rate.

Step-by-step explanation:

Got it right

Answer:

Total outcomes with two dice is:

Outcomes with sum of 7:

Probability:

Outcomes with sum of 5 or 10:

Probability:

Outcomes with same numbers:

Probability:

Answer:

x = 94

Step-by-step explanation:

The sum of the 4 angles in a quadrilateral = 360°

Sum the 4 angles and equate to 360

x + x + 2x - 75 + x - 35 = 360

5x - 110 = 360 ( add 110 to both sides )

5x = 470 ( divide both sides by 5 )

x = 94

Answer:

Area of each sector=[tex]12.6cm^2[/tex]

Step-by-step explanation:

We are given that

Length of each wooden od that connects the center of the fan to its edge ,r=12 cm

Total number of sectors=18

We have to find the approximate area of each sector.

Area of semi-circle=[tex]\frac{1}{2}\pi r^2[/tex]

Using the formula

Area of fan=[tex]\frac{1}{2}\pi (12)^2=72 \pi cm^2[/tex]

Area of each sector=[tex]\frac{area\;of\;fan}{Total\;number\;of\;sectors}[/tex]

Area of each sector=[tex]\frac{72\pi}{18}=\frac{72\times 3.14}{18} cm^2[/tex]

Where [tex]\pi=3.14[/tex]

Area of each sector=[tex]12.56cm^2\approx 12.6 cm^2[/tex]

The complete table of the function is:

[tex]\begin{array}{cccccccc}x & {0} & {1} & {2} & {3} & {4}& {5} & {6} \ \\ f(x) & {72} & {60} & {48} & {36} & {24}& {12} & {0} \ \end{array}[/tex]

The equation missing from the question is:

[tex]y = 72 - 12x[/tex]

To complete the table, we simply calculate the y value for each x value;

When [tex]x = 0[/tex],     [tex]y = 72 - 12 * 0 = 72[/tex]

When [tex]x = 1[/tex],     [tex]y = 72 - 12 * 1 = 60[/tex]

When [tex]x = 2[/tex],     [tex]y = 72 - 12 * 2 = 48[/tex]

When [tex]x = 3[/tex],     [tex]y = 72 - 12 * 3 = 36[/tex]

When [tex]x = 4[/tex],     [tex]y = 72 - 12 * 4 = 24[/tex]

When [tex]x = 5[/tex],     [tex]y = 72 - 12 * 5 = 12[/tex]

When [tex]x = 6[/tex],     [tex]y = 72 - 12 * 6 = 0[/tex]

So, the complete table is:

[tex]\begin{array}{cccccccc}x & {0} & {1} & {2} & {3} & {4}& {5} & {6} \ \\ f(x) & {72} & {60} & {48} & {36} & {24}& {12} & {0} \ \end{array}[/tex]

To create a graph of f(x), we simply type [tex]y = 72 - 12x[/tex] on a drawing tool and the graph will be generated.

See attachment for graph

Learn more about graphs at:

https://brainly.com/question/20106471

Answer:

Step-by-step explanation:

Answer:

m∠TRS = 6°

m∠U = 103°

Step-by-step explanation:

In the given figure,

O is the center

RS ∥ VU

m∠V = 103° &

m∠VRT = 71°

So,

m∠V +  m∠R = 180°                (∵ sum of co-interior angles)

⇒  m∠R = 180° - 103°              (m∠V = 103° is given)

∵ m∠R = 77°    ...(i)

Now,

m∠R =  m∠TRS +  m∠VRT

by putting the values given

⇒  m∠TRS = 77° - 71°

∵ m∠TRS = 6°  

As we know that,

VURT is a cyclic quadrilateral. So,

m∠U +  m∠R = 180°

⇒ m∠U +  77° = 180°            (from equation (i)

∵ m∠U = 180° - 77° = 103°

Answer:

[tex]y = 2x^2 + 1[/tex]

Step-by-step explanation:

The graph you see there is called a parabola. The general equation for the graph is as below

[tex]y = a*x^2 + b[/tex]

To find the equation we need to find the constants a and b. The constant b is just how much we're lifting the parabola by. Notice it's lifted by 1 on the y axis.

To find a it's a little more tricky. Let's use the graph to find a value for a by plugging in values we know. We know that b is 1 from the previous step, and we know that when x=1, y=3. Let's use that!

[tex]3 = a * (1)^2 + 1\\2 = a[/tex]

Awesome, we've found both values. And we can write the result.

[tex]y = 2x^2 + 1[/tex]

I'll include a plotted graph with our equation just so you can verify it is indeed the same.

Step-by-step explanation:

5.

[tex](5 + 4 \sqrt{7} ){x}^{2} + (4 - 2 \sqrt{7} ) x- 1 = 0[/tex]

Simplify both radicals.

[tex](5 + \sqrt{112) {x}^{2} } + (4 - \sqrt{28} )x - 1 = 0[/tex]

Apply Quadratic Formula

First. find the discramnint.

[tex](4 - \sqrt{28} ) {}^{2} - 4(5 + \sqrt{112} )( - 1) = 64[/tex]

Now find the divisor 2a.

[tex]2(5 + \sqrt{112} ) = 10 + 8 \sqrt{7} [/tex]

Then,take the square root of the discrimant.

[tex] \sqrt{64} = 8[/tex]

Finally, add -b.

[tex] - (4 + 2 \sqrt{7} )[/tex]

So our possible root is

[tex] - (4 + 2 \sqrt{7} ) + \frac{8}{10 + 8 \sqrt{7} } [/tex]

Which simplified gives us

[tex] \frac{ 4 + 2 \sqrt{7} }{10 + 8 \sqrt{7} } [/tex]

Rationalize the denominator.

[tex] \frac{4 + 2 \sqrt{7} }{10 + 8 \sqrt{7} } \times \frac{10 - 8 \sqrt{7} }{10 - 8 \sqrt{7} } = \frac{ - 72 - 12 \sqrt{7} }{ - 348} [/tex]

Which simplified gives us

[tex] \frac{6 + \sqrt{7} }{29} [/tex].

6. The answer is 2.

9514 1404 393

Answer:

  5. x = (6 +√7)/29; a=6, b=1, c=29

  6. x = 2

Step-by-step explanation:

The quadratic formula can be used, where a=(5+4√7), b=(4-2√7), c=-1.

  [tex]x=\dfrac{-b+\sqrt{b^2-4ac}}{2a}=\dfrac{-(4-2\sqrt{7})+\sqrt{(4-2\sqrt{7})^2-4(5+4\sqrt{7}})(-1)}{2(5+4\sqrt{7})}\\\\=\dfrac{-4+2\sqrt{7}+\sqrt{16-16\sqrt{7}+28+20+16\sqrt{7}}}{10+8\sqrt{7}}=\dfrac{4+2\sqrt{7}}{2(5+4\sqrt{7})}\\\\=\dfrac{(2+\sqrt{7})(5-4\sqrt{7})}{(5+4\sqrt{7})(5-4\sqrt{7})}=\dfrac{10-3\sqrt{7}-28}{25-112}=\boxed{\dfrac{6+\sqrt{7}}{29}}[/tex]

__

Use the substitution z=3^x to put the equation in the form ...

  z² -3z -54 = 0

  (z -9)(z +6) = 0 . . . . . factor

  z = 9 or -6 . . . . . . . . value of z that make the factors zero

Only the positive solution is useful, since 3^x cannot be negative.

  z = 9 = 3^2 = 3^x . . . . use the value of z to find x

  x = 2

Answer:

Please check out the attachments below to get the answer

Answer:

x = 20

y = 70

Step-by-step explanation:

Since B and D are parallel :

6x - 10 + 3x + 10 = 180 add/subtract like terms

9x = 180 divide both sides by 9

x = 20

angle represented by y and 6x - 10 are supplementary and their sum is 180

y + 6x - 10 = 180 replace x with 20

y + 6*20 - 10 = 180

y + 120 - 10 = 180

y + 110 = 180 subtract 110 from both sides

y = 70

Answer: (3, 18)

Step-by-step explanation: Where the lines corss the x does not go over 10 so the only other option is a 3. If you cut the box hori in half in you mind, the top half being 15-20 and the bottom half bring 10-14, then you can see the lines cross on the top half. Meaning it’s at 18 not 12.

Answer:

80m

Step-by-step explanation:

(20x2) =40m + 40m= 80m

Answer:

D

Step-by-step explanation:

(the line is a / shape, so the slope is positive)

(the line crosses the y axis at (0,-2)

(using the above information, the equation is y=2x-2)

Answer:

y = 2x - 2

Step-by-step explanation:

Start with

y = mx + b

The graph shows the y-intercept -2.

We have y = mx - 2

slope = m = rise/run

The slope is rise of 2 and run of 1, so m = 2.

y = 2x - 2

Answer:

The orginal number is 26.

Step-by-step explanation:

So the units digit can be 3 6 or 9

The tens digit can be 1 2 or 3

So the original number can be 13

31 = 2*13+ (1+3) + 2

31 =? 26 + 4 + 2    

This doesn't work. The right side is 32

26

62 = 2*26 + 8 + 2

62 = 52 + 8 + 2

This is your answer.

3 and 9 won't work because 39 is odd and so is 93. The result has to be even.

The final step. You divided wrong.

8 = 400 / 120  = 10/3

Step-by-step explanation:

The final step. You divided wrong.

[tex] s = \frac{400}{120} = \frac{10}{3} [/tex]