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En una olimpiada matemática, cada estudiante recibe un punto por cada pregunta acertada que tenga, en la siguiente tabla de frecuencias se muestra la clasificación de la cantidad de estudiantes de acuerdo con su puntaje obtenido.



De acuerdo con la tabla, ¿cuál es aproximadamente la desviación estándar?
A.
6,12
B.
7
C.
8,42
D.
9

9514 1404 393

Answer:

  200 m

Step-by-step explanation:

Let d represent the length of the track in meters. The relation of interest is ...

  time = distance/speed

Then the total time to run and walk back is ...

  60 = d/10 + d/5

  600 = d + 2d

  200 = d . . . . . . . divide by 3

The length of the track is 200 meters.

_____

200 m in 20 seconds is a world-record time for a woman; a very good time for a man.

Answer:

18

Step-by-step explanation:

Using PEMDAS, first you do the parenthesis which the value would be 9. Then you divide: 9/ 3= 3. Lastly,  you add 7+3+8=18.

The product will be 18.

Hope this helps! :)

Answer:

3/2

Step-by-step explanation:

Step-by-step explanation:

[tex]x + \frac{1}{2} = 2 \\ x = 2 - \frac{1}{2} \\ x = \frac{3}{2} [/tex]

Answer:

It will be half of the original size.

HOPE I HELPED!

GIVE BRAINLIEST PLEASE!

Step-by-step explanation:

Answer: D

Step-by-step explanation:

The shape, mean, and standard deviation of the sampling distribution of the difference in the two sample proportions is Shape = skewed right, mean = 0.35, standard deviation = 0.05.

In statistics, the standard deviation of a random variable, data is the square root of its variance.

An electronic prize wheel is programmed to land on "win” 25% of the time on weekdays and 10% of the time on weekends, and consecutive plays produce winners independently.

A random sample of 50 outcomes from this machine on a weekday and 100 outcomes from this machine on a weekend.

[tex]P_{1} = 25%\\ =0.25\\P_{2} = 0.10\\[/tex]

[tex]n_{1} = 50\\n_{2} =100[/tex]

Let x be a random variable for weekdays

[tex]x= N[0.25, 0.25\times(1-0.25)/50]\\x = N[0.25, 0.00375][/tex]

Let y be randomly variable for weekdays

[tex]Y= N[0.10, 0.10\times(1-0.10)/100]\\Y= N[0.10, 0.0009][/tex]

Thus, the shape, mean, and standard deviation of the sampling distribution of the difference in the two sample proportions is Shape = skewed right, mean = 0.35, standard deviation = 0.05.

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Answer:

Cos: adjacent / hypotenuse

In a right angled triangle, the cosine of an angle is: The length of the adjacent side divided by the length of the hypotenuse. The abbreviation is cos. cos(θ) = adjacent / hypotenuse. Well Done!

Sin: In mathematics, the sine is a trigonometric function of an angle. The sine of an acute angle is defined in the context of a right triangle: for the specified angle, it is the ratio of the length of the side that is opposite that angle, to the length of the longest side of the triangle.

hope this helps out, if not, i'm sorry

Step-by-step explanation:

Answer:

Sin=O/H

Cos=A/H

Step-by-step explanation:

Sin in full is some, a trigonometric ratio calculated by dividing the opposite over the hypotenuse.

Cos is in full cosine , also a trigonometric ratio calculated by dividing the adjacent over the hypotenuse.

Given:

The triangle ABC rotated 270 degrees clockwise.

The rule of rotation is

[tex](x,y)\to (-y,x)[/tex]

To find:

The coordinates of point B after the given rotation.

Solution:

From the given graph, it is clear that the coordinates of point B are (4,4).

The given rule of rotation is:

[tex](x,y)\to (-y,x)[/tex]

Using this rule, we get

[tex]B(4,4)\to B'(-4,4)[/tex]

The coordinates of point B after the given rotation are (-4,4).

Therefore, the correct option is C.

Answer:

x=60

Step-by-step explanation:

(1/6)(x+6)=11

Multiply both sides by six:

(6)(1/6)(x+6)=11(6)

x+6=66

Take six from both sides:

x+6-6=66-6

x=60

Answer:

< ABC+<QRS=180

m<QRS=180-140=40°

Answer:

Solution given:

<ABC+<QRS=180° {supplementary]

m<QRS=180°-140°=40° is your answer

Answer:

I can't really see the pic :(

Step-by-step explanation:

Answer:

8^2

Step-by-step explanation:

8*8=8^2 or 64

Answer:

2.50 (b)

Step-by-step explanation:

30 divided by 12 is 2.5 which is equal to 2.50 :)

Answer:

b) 2.50

Step-by-step explanation:

$40 - $10 = $30 spent on popcorn

$30/12 = $2.50 per bag

The equation of the line passing through two points (0, 0) and (4, -2) is y = -x/2

The general equation of a line in two variables of the first degree is represented as Ax + By +C = 0, A, B ≠ 0 where A, B and C are constants which belong to real numbers.

Given is a line passing through two points (0, 0) and (4, -2), we need to find the equation of the line,

We know that the equation of the line, passing through two points (x₁, y₁) and (x₂, y₂), is given by:

y-y₁ = y₂-y₁ / x₂-x₁ (x-x₁)

Here, (x₁, y₁) and (x₂, y₂) are (0, 0) and (4, -2), putting the values to finding the equation,

y-0 = -2-0 / 4-0 (x-0)

y = -1/2(x)

y = -x/2

Hence, the equation of the line passing through two points (0, 0) and (4, -2) is y = -x/2

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Answer:

36pie inch²

Step-by-step explanation:

Answer attached

Hope it helps :)

Answer:

− √ ( 9 + y ) 2 > 1

Explanation:

− √ ( 9 + y ) 2 , where  y < − 10

Simplify the expression,

− √ ( 9 + y ) 2 = − ( 9 + y ) = − 9 − y

When  y < − 10 , − y > 10

Subtract  9  from both sides,

− 9 − y > 1  Hence,

− √ ( 9 + y ) 2 > 1

The value of the expression -√(9 + y)² is -9 which is more than -10. So, it is incorrect.

Algebra is the study of abstract symbols, while logic is the manipulation of all those ideas.

The definition of simplicity is making something simpler to achieve or grasp while also making it a little less difficult.

The expression is given below.

⇒ -√(9 + y)²

Simplify the expression, then we have

-√(9 + y)² = 0

(9 + y) = 0

9 + y = 0

y = - 9

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Answer:

3-270x

Step-by-step explanation:

Answer:

[tex]\displaystyle \sin\left(2\sec^{-1}\left(\frac{u}{10}\right)\right)=\frac{20\sqrt{u^2-100}}{u^2}\text{ where } u>0[/tex]

Step-by-step explanation:

We want to write the trignometric expression:

[tex]\displaystyle \sin\left(2\sec^{-1}\left(\frac{u}{10}\right)\right)\text{ where } u>0[/tex]

As an algebraic equation.

First, we can focus on the inner expression. Let θ equal the expression:

[tex]\displaystyle \theta=\sec^{-1}\left(\frac{u}{10}\right)[/tex]

Take the secant of both sides:

[tex]\displaystyle \sec(\theta)=\frac{u}{10}[/tex]

Since secant is the ratio of the hypotenuse side to the adjacent side, this means that the opposite side is:

[tex]\displaystyle o=\sqrt{u^2-10^2}=\sqrt{u^2-100}[/tex]

By substitutition:

[tex]\displaystyle= \sin(2\theta)[/tex]

Using an double-angle identity:

[tex]=2\sin(\theta)\cos(\theta)[/tex]

We know that the opposite side is √(u² -100), the adjacent side is 10, and the hypotenuse is u. Therefore:

[tex]\displaystyle =2\left(\frac{\sqrt{u^2-100}}{u}\right)\left(\frac{10}{u}\right)[/tex]

Simplify. Therefore:

[tex]\displaystyle \sin\left(2\sec^{-1}\left(\frac{u}{10}\right)\right)=\frac{20\sqrt{u^2-100}}{u^2}\text{ where } u>0[/tex]

Its not yet known. We need other numbers and letters!

Answer:

Step-by-step explanation:

3/13

The probability of being dealt a picture card is 3/13

What is Probability?

The probability that an event will occur is measured by the ratio of favorable examples to the total number of situations possible

The value of probability lies between 0 and 1

Given data ,

Let the total number of cards in the deck be = 52 cards

Let the number of picture cards be = A

Now , the picture cards include 4 colors of Jacks , 4 colors of Queens and 4 colors of Kings

So , total number of picture cards = 4 + 4 + 4

                                                        = 12 picture cards

And the probability of drawing a picture cards is P =
number of picture cards / total number of cards in the deck

The probability of drawing a picture cards is P = 12 / 52

                                                                               = 3 / 13

Therefore , the value of P is 3/13

Hence , The probability of being dealt a picture card is 3/13

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Answer:

if I am not wrong I think the anwser will be 2.3

Answer:

It's 3

Step-by-step explanation:

7 can't be divided by 3 so you leave it as a fraction

Answer:

a = 6.7m is the answer.

Step-by-step explanation:

a = ?

b = 6m

c = 9m

According to the Pythagorean theorem,

a² + b² = c²

a² + 6² = 9²

a² + 36 = 81

a² = 81 - 36

a² = 45

a = 6.708

round to the nearest tenth,

a = 6.7m

∴ Janice is 6.7m high up in the air.

Answer:

x = 7

Step-by-step explanation:

Find the point on the graph that has the y-value of 8. Determine its x-value.

Answer:

the mode is 12

Step-by-step explanation:

Arrange the numbers in order : 1 , 3, 6, 6, 9, 9, 12, 12, 12, 12, 12, 15, 15, 15, 15

Then count how many numbers that appears the most, so the number that appears the most is 12, therefore, the mode in the data set is 12 .

9514 1404 393

Answer:

  y = -x -2

Step-by-step explanation:

The line crosses the y-axis at y = -2, so that is the y-intercept.

The slope is the ratio of "rise" to "run." The points on the graph show a "rise" of -3 for a "run" of 3.

  m = rise/run = -3/3 = -1

Then the slope-intercept equation is ...

  y = mx +b . . . . . slope m, y-intercept b

  y = -x -2 . . . . . . . using m=-1, b=-2

Answer:

Its C

Step-by-step explanation:

Diagram c to the left shows the repeating groups of atoms that make up the samples the chemist mixed together.

Atoms are the smallest unit of matter that make up all physical objects. Atoms are composed of three main components: protons, neutrons, and electrons. Protons and neutrons are found in the nucleus of the atom and have a positive charge, while electrons orbit the nucleus and have a negative charge.

here, we have,

we know that,

Atoms can join together to form molecules, which are the building blocks of all matter. Atoms of different elements can join together in different ways to form compounds and these compounds are the basis of all substances. Atoms are also the basis of all chemical reactions and can exist in different physical states, such as solid, liquid, or gas. Atoms can also be combined to form isotopes, which are atoms of the same element with different numbers of neutrons.

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complete question:

11. A chemist mixed two samples together: a brown solid that melts at about 1,300°C and a colorless liquid that melts at about 20°C. She analyzed the results and found two ending substances. One of the ending substances melts at about 250°C. This ending substance is made up of the repeating group of atoms shown above. Which of the diagrams to the left shows the repeating groups of atoms that make up the samples the chemist mixed together?

Answer:

Step-by-step explanation:

Answer:

10/24 and 21/24

Step-by-step explanation:

So the least number that both 12 and 8 will divide into is 24

so 5x2/24 and 7x3/24 so the fractions are 10/24 and 21/24

Answer:

10/24 and 21/24

Step-by-step explanation:

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