Help. pls answer this

To change from rectangular to cylindrical coordinates for points (a) (-8, 8, 8) and (b) (4, 3, 9):

(a) In cylindrical coordinates, the point (-8, 8, 8) is (r, σ, z) = (√128, 3π/4, 8).
(b) For the point (4, 3, 9), the cylindrical coordinates are (r, σ, z) = (5, 0.93, 9).


To convert from rectangular (x, y, z) to cylindrical (r, σ, z) coordinates, follow these steps:
1. Calculate r: r = √(x² + y²)
2. Calculate σ: σ =cylindrical coordinates(y/x) (note that σ is between 0 and 2π)
3. Keep the same z value.

For point (a):
1. r = √((-8)² + 8²) = √128
2. σ = arctan(8/-8) = arctan(-1) = 3π/4 (adjusted to be in the range 0 to 2π)
3. z = 8

For point (b):
1. r = √(4² + 3²) = 5
2. σ = arctan(3/4) ≈ 0.93 (adjusted to be in the range 0 to 2π)
3. z = 9

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Answer:

It is 252

Step-by-step explanation:

Just multiply the base and the height ;-;

The density of the air inside the ball is approximately 11.69 kg/m³.

Density is a unit of measurement for mass per volume.

It is calculated by dividing an object's mass by its volume, and is typically denoted by the symbol "."

In the SI system, the unit of density is typically kilogrammes per cubic metre (kg/m3).

To solve this problem, we need to use the equation for the density of an object:   density = mass / volume

We can find the volume of the basketball by using the formula for the volume of a sphere:  volume = (4/3)πr³

Since the basketball has a diameter of 0.17 meters, its radius is 0.085 meters. When we use this value as a substitute in the volume formula, we get:

volume = (4/3)π(0.085)³ = 0.0002562834 m³

To find the mass of the air inside the ball, we subtract the mass of the deflated ball from the mass of the inflated ball:

mass of air = 0.618 kg - 0.615 kg = 0.003 kg

Now we can calculate the density of the air inside the ball:

density = mass of air / volume = 0.003 kg / 0.0002562834 m³ = 11.69 kg/m³.

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We use integration by calculating the area of the elliptical cross-section and the height of the wedge. Setting up the integral, solving it using u-substitution, and simplifying it, the volume of the wedge is 5000*pi/243 cubic units.

To find the volume of the wedge cut from the elliptical cylinder x^2 + 9y^2 = 25 by the planes z = 0 and z = 3x that is above the xy-plane, we first need to visualize the shape. The elliptical cylinder is a three-dimensional shape that looks like a stretched-out cylinder, with an elliptical cross-section. The plane z = 0 is the xy-plane, which is the flat surface at the bottom of the cylinder. The plane z = 3x is a diagonal plane that intersects the cylinder at an angle. The wedge that we need to find the volume of is the portion of the cylinder that is above the xy-plane and below the plane z = 3x.

To find the volume of this wedge, we need to use integration. We will integrate over the x and y dimensions to find the volume of the shape. We start by finding the limits of integration. The elliptical cylinder has a horizontal axis of length 5 (the square root of 25) and a vertical axis of length 5/3 (the square root of 25/9). We can use these dimensions to set the limits of integration. We will integrate over the x dimension from -5/3 to 5/3 (the limits of the elliptical cross-section) and over the y dimension from -sqrt((25-x^2)/9) to sqrt((25-x^2)/9) (the limits of the elliptical cross-section at each value of x).

Now we need to set up the integral to find the volume. The volume of a wedge can be calculated using the formula V = (1/3)Bh, where B is the area of the base and h is the height of the wedge. In this case, the base is the elliptical cross-section and the height is the distance between the planes z = 0 and z = 3x.

The area of the elliptical cross-section at each value of x and y is given by A = pi * x * 3y. The height of the wedge at each value of x and y is given by h = 3x. So we can set up the integral as follows:

V = integral from -5/3 to 5/3 (integral from -sqrt((25-x^2)/9) to sqrt((25-x^2)/9) of (1/3) * pi * x * 3y * 3x dy) dx

Simplifying this integral, we get:

V = (pi/3) * integral from -5/3 to 5/3 (integral from -sqrt((25-x^2)/9) to sqrt((25-x^2)/9) of 9x^2y dy) dx

Integrating over y, we get:

V = (pi/3) * integral from -5/3 to 5/3 of 9x^2 * [(sqrt((25-x^2)/9))^2 - (-sqrt((25-x^2)/9))^2] dx

Simplifying this integral, we get:

V = (10*pi/9) * integral from -5/3 to 5/3 of x^2 * (25-x^2)^(1/2) dx

This integral can be solved using a u-substitution, where u = 25-x^2 and du/dx = -2x. We get:

V = (10*pi/27) * integral from 0 to 25 of u^(1/2) du

Simplifying this integral, we get:

V = (100*pi/81) * (u^(3/2)/3)| from 0 to 25

V = (100*pi/81) * (125/3)

V = 5000*pi/243

Therefore, the volume of the wedge cut from the elliptical cylinder x^2 + 9y^2 = 25 by the planes z = 0 and z = 3x that is above the xy-plane is 5000*pi/243 cubic units.

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Answer:

y = 1

Step-by-step explanation:

the equation of a horizontal line is

y = c ( c is the value of the y- coordinates the line passes through )

the line passes through (- 5, 1 ) with y- coordinate 1 , then

y = 1 ← equation of horizontal line

Answer: C) y=1

Step-by-step explanation: It couldn't be B or D, seeing as they are both vertical lines. We are left with y=-5 and y=1. The only points that y=-5 pass through have a y-coordinate of -5, and the point in question has a y-coordinate of 1. Your answer is C! Hope this helped.

The statement is true. If B is obtained from A by row operations, the rows of B are linear combinations of the rows of A and vice-versa. (D)

When two matrices A and B are row equivalent, it means they can be obtained from each other through a series of elementary row operations. These row operations include row swapping, row multiplication by a nonzero scalar, and adding/subtracting multiples of one row to another row.

Since row operations preserve the row space of a matrix, the row spaces of A and B remain the same throughout these operations. In other words, the rows of B are linear combinations of the rows of A and vice-versa.

Thus, if A and B are row equivalent, their row spaces are the same, as the span of the rows in both matrices is identical. This supports the statement's truth that if A and B are row equivalent, their row spaces are the same.(D)

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the Wronskian W(y1, y2) is not identically zero, we can conclude that the functions y1(x) = e^x and y2(x) = e^(2x) are linearly independent.

To show that y=e^x and y=e^(2x) are linearly independent, we'll use the Wronskian test. The Wronskian is a determinant that helps determine the linear independence of two functions. For our functions y1(x) = [tex]e^x[/tex] and y2(x) = [tex]e^{2x),[/tex]the Wronskian is given by:

W(y1, y2) = [tex]\left[\begin{array}{ccc}y_1&y_2\\y'_1&y'_2\\\end{array}\right][/tex]
Now, we'll compute the derivatives and populate the matrix:

[tex]y_1'(x) = e^x\\y_2'(x) = 2e^{2x}[/tex]

W(y1, y2) =[tex]e^x2e^{2x}-e^xe^{2x}[/tex]

Next, we'll compute the determinant of this matrix:

[tex]W(y1, y2) = (e^x * 2e^{2x)}) - (e^x * e^{2x}))\\W(y1, y2) = e^{3x)} (2 - 1)\\W(y1, y2) = e^{3x}\\\\[/tex]
Since the Wronskian W(y1, y2) is not identically zero, we can conclude that the functions [tex]y1(x) = e^x[/tex]and [tex]y2(x) = e^{2x}[/tex] are linearly independent.

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There is not sufficient evidence to conclude that infestation by spider mites induces resistance to wilt disease caused by the Verticillium fungus in cotton plants at the 1% level.

The question being investigated is whether infestation by spider mites can induce resistance to wilt disease caused by the fungus Verticillium in cotton plants. The experiment involved two groups of cotton plants - one group was infested with spider mites, while the other group served as controls. After two weeks, the mites were removed and both groups were inoculated with the Verticillium fungus. The number of plants that developed symptoms of wilt disease was recorded for each group.

To test whether infestation by spider mites can induce resistance to wilt disease, we can use a hypothesis test. The null hypothesis (H0) is that there is no difference in the proportion of plants that develop wilt disease between the mites and no mites groups, while the alternative hypothesis (Ha) is that the mites group has a lower proportion of plants with wilt disease compared to the no mites group.

We can use a chi-square test for independence to determine whether the data provide sufficient evidence to reject the null hypothesis at the 1% level. The test statistic is calculated as follows:

chi-square = (ad - bc)^2 / [(a+b)(c+d)]

where a = number of plants in the mites group with wilt disease, b = number of plants in the mites group without wilt disease, c = number of plants in the no mites group with wilt disease, and d = number of plants in the no mites group without wilt disease.

Using the data from the table, we can calculate the test statistic as follows:

chi-square = (14*28 - 18*26)^2 / [(14+18)(28+26)] = 1.079

The degrees of freedom for the chi-square test is (2-1)*(2-1) = 1. The critical value of chi-square at the 1% level with 1 degree of freedom is 6.635.

Since the calculated chi-square value (1.079) is less than the critical value (6.635), we fail to reject the null hypothesis.

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Answer: 8 to 40

6:30

2/10

Step-by-step explanation:To check if this is the answer you can multiply the first number of each of these ratios by 5. (We multiply them by five because it is the second number in the ratio 1:5)

8 times 5 equals 40 -so this one is right

6 times 5 equals 30 -yep this one is right too

2 times 5 equals 10 -yeperdoodle

Yeah..so these are the answers! let me know if this helps you out.

1. Affordably presented by objects or environments, such as a ball providing the opportunity to practice grasping, throwing, and catching.
2. Individuals perceive these affordances and decide to engage with them, based on their current motor abilities and developmental stage.
3. Through interacting with affordances, individuals practice and develop their motor skills by attempting, refining, and mastering the actions associated with affordance.

Affordably is a term used to describe the relationship between an individual's perception of their environment and their ability to interact with it. In terms of motor development, affordances refer to the opportunities for movement that the environment presents. These opportunities can be both physical and social and can include objects to manipulate, spaces to explore, and people to interact with.

The concept of affordance is important for motor development because it provides children with opportunities to practice and refine their motor skills. As children explore their environment, they are able to perceive the various affordances that it presents, and they can use these affordances to develop their motor skills.

For example, a child may perceive that a box can be used as a stepping stool, and they may use this affordance to climb up onto a table. In doing so, they are developing their balance, coordination, and strength. Similarly, a child may perceive that a ball can be thrown, caught, and bounced, and they can use these affordances to develop their hand-eye coordination, spatial awareness, and timing.

Overall, affordance plays an important role in motor development by providing children with opportunities to explore and interact with their environment and to develop their motor skills in the process.
Affordance contributes to motor development by providing opportunities for individuals to interact with their environment, which in turn helps them develop and refine their motor skills. Affordance refers to the potential actions or uses that an object or environment provides to an individual. In the context of motor development, affordances can be seen as opportunities for practicing and enhancing motor abilities.


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The value of the function 8s/ 2s^2−25s using inverse  Laplace transform  is equal to 4e^(25t/2).

Function is equal to,

8s/ 2s^2−25s

Value of 's' after factorizing the denominator we get,

2s^2−25s = 0

⇒ s( 2s -25 ) =0

⇒ s =0 or s =25/2

Now apply partial fraction decomposition we get,

8s/ 2s^2−25s = A/s + B /(2s -25)

Simplify it we get,

⇒ 8s = A(2s -25) + Bs

Now substitute s =0 we get,

⇒ 0 = A (-25) + 0

⇒ A =0

and s = 25/2

⇒8(25/2) = A(2×25/2 -25 ) + B(25/2)

⇒100 = B(25/2)

⇒B = 8

Now ,

8s/ 2s^2−25s = 0/s + 8 /(2s -25)

⇒ 8s/ 2s^2−25s = 8 /(2s -25)

Take inverse Laplace transform both the side we get,

L⁻¹ [8s / (2s^2 - 25s)] = L⁻¹ [8/(2s - 25)]

Apply , L⁻¹ [1/(as + b)] = (1/a)e^(-bt/a),

here,

a = 2 , b = -25

L⁻¹ [8s / (2s^2 - 25s)]

= L⁻¹ [8/(2s - 25)]

= (8/2) e^(25t/2)

= 4e^(25t/2)

Therefore, the value of  inverse Laplace transform for the given function is equal to 4e^(25t/2)

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The above question is incomplete, the complete question is:

Find the inverse Laplace transform of 8s/ 2s^2−25s.

Substituting x = 1, we get:

y''(1) = 16/√3.

To solve the differential equation (y^(1/3)x)dy/dx = 1/x, we need to separate the variables and integrate both sides with respect to their respective variables.

First, we can rewrite the equation as:

dy/y^(1/3) = (dx/x)

Next, we can integrate both sides:

∫dy/y^(1/3) = ∫dx/x

Integrating the left side, we use the substitution u = y^(1/3), du = (1/3)y^(-2/3)dy:

3∫du/u = ln|u| + C1 = ln|y^(1/3)| + C1

Integrating the right side, we get:

∫dx/x = ln|x| + C2

Putting the two integrals together, we have:

ln|y^(1/3)| = ln|x| + C

where C = C2 - C1

To solve for y, we can exponentiate both sides:

|y^(1/3)| = e^C|x|

Since y(1) = 4, we can use this initial condition to solve for the constant C:

|4^(1/3)| = e^C|1|

C = ln(4^(1/3)) = ln(2/√3)

Substituting C into the equation above, we get:

|y^(1/3)| = e^(ln(2/√3))|x| = (2/√3)|x|

Squaring both sides and solving for y, we get:

y = (2/√3)^3x^3 = (8/3√3)x^3

Finally, to express y''(1) in terms of x, we take the second derivative of y:

y = (8/3√3)x^3

y' = 8x^2/√3

y'' = 16x/√3

Substituting x = 1, we get:

y''(1) = 16/√3.

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To create an algorithm that decides whether there is a string w ∈ Σ* such that w is in neither L1 nor L2, using the closure properties of regular languages, Compute the complements of the regular languages L1 and L2, denoted as L1' and L2', using property C (closed under complement).

To decide whether there exists a string w in neither L1 nor L2, we can use the following algorithm:
1. Take the complement of L1 and L2, denoted as L1' and L2' respectively, using property C.
2. Take the intersection of L1' and L2', denoted as L3, using property B.
3. Take the reverse of L3, denoted as L4, using property D.
4. Concatenate L1 and L2, denoted as L5, using property E.
5. Take the complement of L5, denoted as L5', using property C.
6. Take the intersection of L4 and L5', denoted as L6, using property B.
7. If L6 is empty, output "NO". Otherwise, output "YES" and provide any string w in L6.
Explanation:
Step 1 ensures that L1' and L2' contain all strings that are not in L1 and L2 respectively.
Step 2 finds the strings that are not in either L1 or L2, i.e., the intersection of L1' and L2'.
Step 3 reverses the strings in L3, since the question asks for a string w and not a language.
Step 4 concatenates L1 and L2 to ensure that we consider all possible strings, not just those that are in L1 or L2 separately.
Step 5 takes the complement of L5 to find the strings that are not in L5, which are the strings that are not in either L1 or L2.
Step 6 finds the intersection of the reversed strings in L4 and the strings not in L5, which are the strings that are not in L1 or L2. If L6 is empty, it means there is no such string w, and we output "NO". Otherwise, we output "YES" and provide any string w in L6.
To create an algorithm that decides whether there is a string w ∈ Σ* such that w is in neither L1 nor L2, using the closure properties of regular languages, follow these steps:
1. Compute the complements of the regular languages L1 and L2, denoted as L1' and L2', using property C (closed under complement).
2. Compute the intersection of the complements L1' and L2', denoted as L3 = L1' ∩ L2', using property B (closed under intersection).
3. Check if L3 is empty or not. If L3 is not empty, it means there exists a string w ∈ Σ* that is in neither L1 nor L2.
This algorithm leverages the closure properties of regular languages to find a string that is not present in both L1 and L2.

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Answer: 33 units²

Step-by-step explanation:

      We have four triangles that we will find the area for. Since we have two sets of equivalent triangles, we will use A = BH for both different sizes, but we won't divide by two (since we have two).

A = BH

A = (3)(9)

A = 27 units²

A = BH

A = (3)(2)

A = 6 units²

      Now, we will add these two sets of triangles together.

A = 27 units² + 6 units²

A = 33 units²

The value of n when t = 4 can be found using the given data points and an appropriate mathematical model. Since the problem does not specify the nature of the relationship between n and t, we will assume a linear relationship and use the slope-intercept form of a straight-line equation to find the value of n when t = 4.

First, we need to find the slope of the line. Using the two data points provided, we can calculate:

slope = (change in n) / (change in t) = (400 - 150) / (1 - 0) = 250

Next, we can use the point-slope form of a line equation to find the equation of the line:

n - 150 = 250(t - 0)
n = 250t + 150

Finally, we can substitute t = 4 into the equation to find the value of n:

n = 250(4) + 150 = 1150

Therefore, the value of n when t = 4 is 1150.

In summary, to find the value of n when t = 4, we assumed a linear relationship between n and t and used the two given data points to calculate the slope of the line. We then used the point-slope form of a line equation to find the equation of the line, and substituted t = 4 into the equation to find the value of n.

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Effect size measure (r²) for this independent-measures experiment is 0.412.

We first need to find the value of t and the degrees of freedom (df).

From the information given, t(30) = 6.35, which means that the t-value is 6.35 and the degrees of freedom are 30.

We can use the following formula to calculate r²:

r² = t² / (t² + df)

Plugging in the values we have:

r² = (6.35)² / [(6.35)² + 30] = 0.412

Therefore, the effect size measure (r²) for this independent-measures experiment is 0.412. This indicates a large effect size.

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If N = 25 and K = 5, the degrees of freedom (df) you would use is C. 5,20.

This is because the formula for degrees of freedom in this case is (K-1)(N-1), which gives us (5-1)(25-1) = 4x24 = 96, and we divide by the total sample size (N) to get 96/25 = 3.84.

Since we cannot use a decimal for degrees of freedom, we round down to the nearest whole number, which gives us 3.

Therefore, the degrees of freedom for this scenario is 5-1 = 4 for the numerator and 25-1 = 24 for the denominator, which gives us a final answer of C. 5,20.

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Answer:

40%

Step-by-step explanation:

We Know

The price of 1 kg of prawns increases from $28 to $35.

Find the percentage increase in price.​​

We Take

(35 ÷ 25) x 100 = 140%

Then We Take

140% - 100% = 40%

So, the percentage increase in the price is 40%.

The statement "if B is a 3x3 matrix, and det(B) = -4, then det([tex]2BB^tB^{-1[/tex]) = -8" is false.

If B is a 3x3 matrix, and det(B) = -4, then det([tex]2BB^tB^{-1[/tex]) = -8. Here are the terms I will include in my answer: matrix, determinant, transpose, and inverse.

1. Determine det(B)
Given: det(B) = -4

2. Compute det(2B)
The determinant of a scalar multiple of a matrix is the scalar raised to the power of the matrix's dimension multiplied by the determinant of the matrix. Since the matrix is 3x3, we have:
det(2B) = ([tex]2^3[/tex]) * det(B) = 8 * (-4) = -32

3. Compute det([tex]B^t[/tex])
The determinant of a matrix and its transpose are equal, so:
det([tex]B^t[/tex]) = det(B) = -4

4. Compute det([tex]B^{-1[/tex])
For an invertible matrix, the determinant of its inverse is the reciprocal of the determinant:
det([tex]B^{-1[/tex]) = 1/det(B) = 1/(-4) = -1/4

5. Calculate det([tex]2BB^tB^{-1[/tex])
Using the property of determinants that det(AB) = det(A) * det(B), we have:
det([tex]2BB^tB^{-1[/tex]) = det(2B) * det([tex]B^t[/tex]) * det([tex]B^{-1[/tex]) = -32 * (-4) * (-1/4) = -32

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Ans: B (=20)

p/s: sorry i use my calculator :')))) bc it's too long. you can do it by substituting the x values of each one according to the answer into the given equation.If there are any mistakes, please forgive me :'))))

Ok done. Thank to me >:333

Answer:

x= 200

Step-by-step explanation:

(200)2 - 1 = 399

Answer:

Step-by-step explanation: well what we can do so far is this: x2-1=399

                                                                                                        x2+1=399+1

So now that we have x2 by itself, the equation will look something like this

x2=400

because its x2 AND NOT x1, we will have to take the SQUARE ROOT.

x=±√400

x= either positive 20 or -20!

The zoo keeper is 5.5 feet tall.

When the corresponding properties of two or more triangles are compared, and there is a common relations among them, then the triangles are said to be similar. Thus their corresponding sides may be compared in form of ratio.

In the question, the giraffe casts a shadow as given. Then by comparison, the height of the zoo keeper (h) can be determined as follows:

4/ 12 = h/ 16.5

12h = 4*16.5

      = 66

h = 66/ 12

  = 5.5

The zoo keeper is 5.5 feet tall.

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The number of ways that endpoint P that is perpendicular to line n is One way.

In a plane, two lines are parallel if they lie in the same plane and never intersect, no matter how far they are extended. If a point is between two parallel lines, it lies on a line that is perpendicular to both of the parallel lines.

We can draw a line that passes through endpoint P and is perpendicular to line n. This line will intersect line m at a right angle. Since there is only one line that passes through a point and is perpendicular to another line, there is only one line that can be drawn from endpoint P that is perpendicular to line n.

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To find T, N, and k for the space curve r(t) = -7ti - (7a cosh(t/a))j with a > 0.6, follow these steps:

1. Calculate the first derivative, r'(t), to find the tangent vector T:
r'(t) = -7i - (7/a sinh(t/a))j
To find the unit tangent vector T, normalize r'(t):
T = r'(t) / ||r'(t)||

2. Calculate the second derivative, r''(t), to find the normal vector N:
r''(t) = - (7/a² cosh(t/a))j
To find the unit normal vector N, normalize r''(t):
N = r''(t) / ||r''(t)||

3. Calculate the curvature k:
k = ||r'(t) x r''(t)|| / ||r'(t)||³

In summary, find the first and second derivatives of r(t), normalize them to get T and N, and compute the curvature k using the given formula.

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Answer:

y= -5(x+6)^2 +4

Step-by-step explanation:

The solution to the equation for x is given as follows:

x = 2.92.

The equation for x in this problem is solved applying the proportions of the problem.

The equivalent side lengths are given as follows:

Hence the proportional relationship to obtain the value of x is given as follows:

27/21 = (9x - 19)/(-9x + 83)

Applying cross multiplication, we obtain the value of x as follows:

21(9x - 19) = 27(-9x + 83)

432x = 1263

x = 1263/432

x = 2.92.

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Taking the difference between the ages, we can see that  her grandmother is 56 years older than her.

To find how many years older his her grandmother, we just need to take the difference between both of their ages. (remember that a difference is just a subtraction)

Then we will take the age of the grandmother and we will subtract the age of Anita.

We will get the difference:

D = 68 - 12

D = 56

We can see that her grandmother is 56 years older than her.

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In mathematics, these extreme probabilities are expressed as 0 (impossible) and 1 (certain). This means a probability number is always a number from 0 to 1.

Probability can also be written as a percentage, which is a number from 0 to 100 percent.

The numerical expressions are:

(2 + 4) x 7 = 42

(12 ÷ 3) x 5 = 20

A mathematical expression is made up of integers and mathematical operators including addition, multiplication, subtraction, and division.

A number can be expressed in numerous ways, including word form and numerical form.

A numerical expression is a mathematical statement that only contains numbers and one or more operation symbols. Addition, subtraction, multiplication, and division are examples of operation symbols. It can alternatively be expressed using the radical symbol (square root symbol) or the absolute value symbol.

The numerical expressions are:

(2 + 4) x 7 = 42

(12 ÷ 3) x 5 = 20

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