Find the rate of change of total​ revenue, cost, and profit with respect to time. Assume that​ R(x) and​ C(x) are in dollars. ​R(x)equals2 x​, ​C(x)equals0.01 x squared plus 0.3 x plus 30​, when xequals30 and StartFraction dx Over dt EndFraction equals9 units per day

Answer:

Step-by-step explanation:

When you have several evaluations to do, it is often convenient to put the formula into a graphing calculator or spreadsheet.

__

If you must evaluate a polynomial by hand, it is often easier if the expression is written in "Horner form":

  g(x) = (-2x +3)x -5

Then we have ...

  g(-2) = (-2(-2) +3)(-2) -5 = 7(-2) -5 = -19

  g(0) = (-2(0) +3)(0) -5 = -5

  g(3) = (-2(3) +3)(3) -5 = (-3)(3) -5 = -14

Answer:

solution,

[tex] \frac{ac}{ef} = \frac{cb}{fd} \\ or \: \: \frac{12}{y} = \frac{15}{5} \\ or \: 15 \times y = 12 \times 5( \: cross \: multiplication) \\ or \: 15y = 60 \\ or \: y = \frac{60}{15} \\ y = 4[/tex]

Hope this helps...

Good luck on your assignment..

Answer:

The value of y is 4

Step-by-step explanation:

What is similarity ?

In Euclidean geometry, two objects are similar if they have the same shape, or one has the same shape as the mirror image of the other.

Given,

ΔACB~ΔEFD

The proportional sides are equal.

[tex]\frac{AC}{EF}=\frac{CB}{FD}=\frac{AB}{DE} \\\frac{12}{y}=\frac{15}{5} \\y=12*\frac{5}{15}\\\\ y=4[/tex]

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Answer:

0

Step-by-step explanation:

√12 can be rewritten as √2²·3 = 2√3

√75 can be rewritten as √5²·3 = 5√3

2/5 * 5 = 2

so

2√3 - 2/5 * 5√3 = 2√3 - 2√3 = 0

Answer:

0

Step-by-step explanation:

The function is f(x)= 2x+1/x+3.

A work domain is a set of all possible inputs for a job. For example, the domain f (x) = x² is all real numbers, and the domain g (x) = 1 / x is all real numbers except x = 0. And we can define the special functions of its most limited domains.

The function domain f (x) is a set of all values ​​defined by the function, and the scope of the function is a set of all values ​​taken by f. (In grammar school, you probably call the domain a set of substitutes and a set of solutions.

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Answer:

B

Step-by-step explanation:

i got it right! :)

Answer:

Step-by-step explanation:

We assume you want the integral ...

  [tex]\displaystyle\int_4^{14}{\sqrt{\ln{x}}}\,dx[/tex]

The width of each interval is 1/6 of the difference between the limits, so is ...

  interval width = (14 -4)/6 = 10/6 = 5/3

Then the point p[n] at the left end of each interval is ...

  p[n] = 4 +(5/3)n

__

Trapezoidal Rule

The area of a trapezoid is the product of its average base length multiplied by the width of the trapezoid. Here, the "bases" are the function values at each end of the interval. The integral according to the trapezoidal rule can be figured as ...

  [tex]\dfrac{5}{3}\sum\limits_{n=0}^{5}\left(\dfrac{f(p[n])+f(p[n+1])}{2}\right)[/tex]

  integral ≈ 14.559027

If you're doing this on a spreadsheet, you can avoid evaluating the function twice at the same point by using a weighted sum. Weights are 1, 2, 2, ..., 2, 1.

__

Midpoint Rule

This rule uses the area of the rectangle whose height is the function value at the midpoint of the interval.

  [tex]\dfrac{5}{3}\sum\limits_{n=0}^{5}{f(p[n+\frac{1}{2}])}[/tex]

  integral ≈ 14.587831

__

Simpson's Rule

This rule gives the result of approximating the function over each double-interval by a parabola. It is like the trapezoidal rule in that the sum is a weighted sum of function values. However, the weights are different. Again, multiple evaluations of the function can be avoided by using a weighted sum in a spreadsheet. Weights for 6 intervals are 1, 4, 2, 4, 2, 4, 1. The sum of areas is ...

  [tex]\dfrac{10}{3}\sum\limits_{n=0}^{2}{\left(\dfrac{f(p[2n])+4f(p[2n+1])+f(p[2n+2])}{6}\right)}[/tex]

  integral ≈ 14.577542

Answer:

y-1 = 3(x +2)

Step-by-step explanation:

Ok, so the point-slope form is:

y-k = m(x-h)  where m is the slope and (h,k) is the given point.

Since you are given  m = 3 ,  and (h,k) = (-2,1)

y-1 = 3(x +2)

Since your question specified using the point-slope form, make sure you use this equation when answering it. Otherwise, you may get it wrong.

ANSWER:

EXPLANATION:

A simple random sample of size has mean and standard deviation. Construct a confidence interval for the population mean. The parameter is the population The correct method to find the confidence interval is the method.

The sample size is not given. Mean and Standard Deviation are not given.

To construct a confidence interval for the population mean, first find out the margin of error of the sample mean. This is why you need a confidence interval. If you are 90% confident that the population mean lies somewhere around the sample mean then you construct a 90% confidence interval.

This is equivalent to an alpha level of 0.10

If you are 95% sure that the population mean lies somewhere around the sample mean, your alpha level will be 0.05

In summary, get the values for sample size (n), sample mean, and sample standard deviation.

Make use of a degrees of freedom of (n-1).

Answer:

y = Vx - 5

Step-by-step explanation:

shift down is -5

y = Vx - 5 is the function whose graph is the graph of y= Vx, but is translated 5 units downward.

Graph is a mathematical representation of a network and it describes the relationship between lines and points.

The function y = Vx represents the square root function, which is a graph of a half of a parabola opening upwards and passing through the point (0, 0).

To translate this function 5 units downward, we need to subtract 5 from the function. Therefore, the function we need is:

y = Vx - 5

This is the square root function shifted downward by 5 units.

The graph of this function will be the same as the graph of y = Vx, but shifted 5 units downward.

Hence, y = Vx - 5 is the function whose graph is the graph of y= Vx, but is translated 5 units downward.

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Step-by-step explanation:

The difference between. Each numbers is 5 so, it's answer is 22 and 27

Answer:

Area = 7 square units

Perimeter = 14 units

Step-by-step explanation:

The shape is made up of 7 identical squares and, we are told the side length of each square is 1 unit.

==>Find area of the shape by calculating the area of 1 square, then multiply by the number of square used in the construction.

Thus, area of 1 square = s² = 1² = 1 square units.

Area of shape = 7 × 1 square units = 7 square units

==>Find the Perimeter of the shape by adding all the lengths of the boundary formed by the square to make up the shape.

(Check attachment to understand how we got the measurement of the boundary)

The perimeter = 1 + 1 + 1 + ½ + ½ + 1 + 1 + 1½ + ½ + 1 + 1 + 4 = 14 units

Answer:

39°

Step-by-step explanation:

==>Given:

Shadow length = 20ft

Flag height = 16ft

==>Required:

Angle of elevation of sun (θ)

==>Solution:

To calculate the angle of elevation of the sun, recall the trigonometry formula SOHCAHTOA.

We are given adjacent side = 20ft, and opposite side = 16ft

Therefore, we would use TOA, which is:

tan θ = Opposite/Adjacent

tan θ = 16/20

tan θ = 0.8

θ = 38.6598083 ≈ 39°

Angle of elevation of the sun = 39°

Answer:

option 1 both statements are true

Step-by-step explanation:

Prove by PMI -- Principle of Mathematical  Induction

1) n³ + 2n

n= 1 , 1³ +2*1 = 1+2 = 3 = 3*1   ---->divisible by 3

n = 2 ; 2³ + 2*2 = 8+4 = 12  = 3*4  ----> is divisible by 3

Assume that It is valid for n = k ;  

[tex]k^{3}+2k[/tex] = 3*m -----(I) , for all m ∈ N

We have to prove for n =k +1 , the statement is true.

n = k+1, [tex](k+1)^{3}+2(k +1) =k^{3}+3k^{2}+3k +1 +2k +2[/tex]

                                           = k³ + 3k² + 3k + 3 + 2k

                                           =  k³ +  2k + 3k² + 3k + 3

                                           = 3m + 3 (k² + k + 1)

                                          = 3(3 + [k² + k + 1] ) is divisible by 3

Therefore, this statement is true

2) [tex]5^{2n}-1\\[/tex]

[tex]n=1 ; 5^{2}-1 = 25 -1 = 24 divisible by 24\\\\n = 2 ; 5^{2*2}-1 = 5^{4}-1 = 625 - 1 = 624 divisible by 24[/tex]

This statement is also true

Answer:

Width is 15, length is 35.We can check our answer by multiplying the length by 2 and the width by two in order for the perimeter to be equal to 200.15 times 2 is 30 and 35 times two equals 70.70+30=100 so our solution satisfies our problem.

Step-by-step explanation:

Let the width be x.Then the length should be x+20.The farmer can’t use more than 100 ft of fencing and by mentioning enclosing a rectangle area for a pigpen, we can tell that 100 is the perimeter.So 2(x+20) + 2(x)=100.2x+ 40 + 2x=100.4x+40=100.4x=60.X is 15 which is the width so then the length is 35.

Answer:

Step-by-step explanation:

Product of 5 and a number:  5n

Six more than that would be 5n + 6

Finally, "six more than the product of 5 and a number, decreased by one" would be

5n + 6 - 1, or 5n + 5

Answer: A) 6 + 5n - 1

Step-by-step explanation: edge. 2022

Answer: 30 folders - 15 folders which she keeps = 15 folders; 15 folders / 3 friends = 5 folders per firend.

Step-by-step explanation:

Answer:

x= (30 -15)/3

Step-by-step explanation:

If we call x the number each friend gets, then the equation is:

Solving this we get:

Each friend gets 5 folders

Answer:

solution,

[tex]48 > 2x - 10 \\ 48 + 10 > 2x \\ \frac{58}{2} > \frac{2x}{2} \\ 29 > x \\ x < 29[/tex]

but,

[tex]2x - 10 > 0 \\ \frac{2x}{2} > \frac{10}{2} \\ x > 5 \\ \\ 5 < x < 29 \: is \: the \: answer.[/tex]

Hope this helps...

Good luck on your assignment..

The range of value of x is 5 < x < 29.

A quadrilateral in geometry is a four-sided polygon with four edges and four corners.

Given:

A quadrilateral ABCD.

From the diagram,

2x - 10 < 48

2x < 58

x < 29.

And 0 < 2x - 10

10 < 2x

5 < x

Therefore, the range is 5 < x < 29.

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Answer:

60%

Step-by-step explanation:

Total Cards = 5

Even Numbers = 3

P(even) = 3/5

In %age:

=> 60%

Answer:

60%

Step-by-step explanation:

The numbers that are even from the list are 2, 4, and 6.

3 numbers are even out of 5 total numbers.

3/5 = 0.6

P(even) = 60%

Answer:

(C)[tex]6t^2+5[/tex]

Step-by-step explanation:

Given the distance, d(t) of a particle moving in a straight line at any time t is:

[tex]d(t) = 2t^3 + 5t - 2, $ where t is given in seconds and d is measured in meters.[/tex]

To find an expression for the instantaneous velocity v(t) of the particle at any given point in time, we take the derivative of d(t).

[tex]v(t)=\dfrac{d}{dt}\\\\v(t) =\dfrac{d}{dt}(2t^3 + 5t - 2) =3(2)t^{3-1}+5t^{1-1}\\\\v(t)=6t^2+5[/tex]

The correct option is C.

Answer:

6t2+5

Step-by-step explanation:

Answer:

P-value =0.062

At a signficance level of 0.05, there is not enough evidence to support the claim that the unemployment rate is less than 5%.

Step-by-step explanation:

This is a hypothesis test for a proportion.

The claim is that the unemployment rate is less than 5%.

Then, the null and alternative hypothesis are:

[tex]H_0: \pi=0.05\\\\H_a:\pi<0.05[/tex]

The significance level is 0.05.

The sample has a size n=1500.

The sample proportion is p=0.041.

[tex]p=X/n=61/1500=0.041[/tex]

The standard error of the proportion is:

[tex]\sigma_p=\sqrt{\dfrac{\pi(1-\pi)}{n}}=\sqrt{\dfrac{0.05*0.95}{1500}}\\\\\\ \sigma_p=\sqrt{0.000032}=0.0056[/tex]

Then, we can calculate the z-statistic as:

[tex]z=\dfrac{p-\pi+0.5/n}{\sigma_p}=\dfrac{0.041-0.05+0.5/1500}{0.0056}=\dfrac{-0.0087}{0.0056}=-1.5401[/tex]

This test is a left-tailed test, so the P-value for this test is calculated as:

[tex]\text{P-value}=P(z<-1.5401)=0.062[/tex]

As the P-value (0.062) is greater than the significance level (0.05), the effect is  not significant.

The null hypothesis failed to be rejected.

There is not enough evidence to support the claim that the unemployment rate is less than 5%.

Answer:

The answer is explained below

Step-by-step explanation:

What use are statistics if there is no engineer to use them? In other words, a statistician corrects, improves, reinforces, and supports an engineer in building / designing / developing a new product and / or improving an existing product.

The statistician provides a special kind of vision through which I see the same problem in a completely different vision. So you can see the strengths, weaknesses of my product and the promise of improvements that can be made.

Each class of statistics is essential for a student to see and understand a problem in a whole new way where it is much easier to understand information.

Answer:

Length= 30 in

Width= 10 in

Step-by-step explanation:

Let the width of the rectangle be x in.

Length of rectangle

= 3 (width)

= 3x

Perimeter of rectangle= 2(length) +2(width)

80= 2(3x) +2(x)

80= 6x +2x

8x= 80 (simplify)

x= 80 ÷8 (÷8 on both sides)

x= 10

Thus width of rectangle= 10 in

Length of rectangle

= 3(10)

= 30 in

Answer:

The simplified expression is:

[tex]\dfrac{-7}{10}p^2q^2r+\dfrac{1}{2}pq^2r-\dfrac{11}{28}pqr^2+\dfrac{1}{8}p^2qr[/tex]

Step-by-step explanation:

To find:

[tex]-\dfrac{1}{2}p^{2} q^{2} r+\dfrac{1}{3}p q^{2} r-\dfrac{1}{4}p q r^{2}-\dfrac{1}{5}rq^{2} p^{2} +\dfrac{1}{6}rq^{2} p-\dfrac{1}{7}r^{2}pq+\dfrac{1}{8}rp^{2}q[/tex]

Solution:

We can see that pqr having power 1 is common throughout.

Let us take it common to make the expression simpler and then we will add by taking LCM:

[tex]\Rightarrow pqr(-\dfrac{1}{2}p q+\dfrac{1}{3}q-\dfrac{1}{4}r-\dfrac{1}{5}pq+\dfrac{1}{6}q-\dfrac{1}{7}r+\dfrac{1}{8}p)\\\Rightarrow pqr(-\dfrac{1}{2}p q-\dfrac{1}{5}pq+\dfrac{1}{3}q+\dfrac{1}{6}q-\dfrac{1}{4}r-\dfrac{1}{7}r+\dfrac{1}{8}p)\\\Rightarrow pqr(\dfrac{-5pq-2pq}{2\times 5}+\dfrac{2q+q}{2 \times 3}+\dfrac{-7r-4r}{7 \times 4}+\dfrac{1}{8}p)\\\Rightarrow pqr(\dfrac{-7pq}{10}+\dfrac{3q}{6}+\dfrac{-11r}{28}+\dfrac{1}{8}p)\\\Rightarrow pqr(\dfrac{-7}{10}pq+\dfrac{1}{2}q+\dfrac{-11}{28}r+\dfrac{1}{8}p)[/tex]

Now, multiplying pqr again to the expression:

[tex]\Rightarrow \dfrac{-7}{10}p^2q^2r+\dfrac{1}{2}pq^2r-\dfrac{11}{28}pqr^2+\dfrac{1}{8}p^2qr[/tex]

So, the answer is:

[tex]\dfrac{-7}{10}p^2q^2r+\dfrac{1}{2}pq^2r-\dfrac{11}{28}pqr^2+\dfrac{1}{8}p^2qr[/tex]

Answer:

D.y-4=f(x+3)

Step-by-step explanation:

The correct translation would be y-4 because the y-coordinate moves down 4 units and f(x+3) because the x-coordinate would move 3 spaces to the right.

Hope this helps!!! PLZ MARK BRAINLIEST!!!

The equation of the translation image of the function is  y - 4 = f(x + 3).

which is the correct answer would be an option (D).

A graph can be defined as a pictorial representation or a diagram that represents data or values.

Vertical shifting of a graph is done by adding any arbitrary constant to the function in shifting.

For example, If shift up by 1 unit,  add 1 to the function

If shift down by 4 units, subtract 4 from the function

To determine the graph of y (x) is translated as 3 units right and 4 units down.

The x-coordinate will increase by 3 if we move it to the right.

If we shift it downward, it will become negative and read as y - 4.

So y - 4 = f(x + 3)

Therefore, the equation of the translation image of the function is  y - 4 = f(x + 3).

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Answer:

1/16

Step-by-step explanation:

Here,

Vertex =(3,5)

x= -1, y=6

Simply,eqn of parabola is given by ax^2+bx+c=y

So, coefficient of squared term (x^2) is 'a'

Therefore, we've to find the value of a

Moving on to solution:

a-b+c=6 ___(i) (by putting the given values of x and y in eqn of parabola )

We know that,

Vetex=(-b/2a, ( 4ac-b^2)/4a)

(3,5) = (-b/2a , (4ac-b^2)/4a)

Equating corresponding sides,we get

3= -b/2a

b=-6a___(ii)

Again,

5=(4ac-b^2)/4a

5=(4ac/4a) - (b^2/4a)

5= c- (36a^2/4a) (by putting value of b from eqn ii )

5= c-9a___(iii)

Now,moving back to the first eqn

a+6a+5+9a=6

16a=1

therefore,a=1/16

Hence ,the required value of coefficient of squared term is 1/16.

I tried my best to give clear explanation as much as I know. It's just we've have to find the value of a . For that, you can use any method you find easier.

Answer:

[tex]\frac{1}{256}[/tex]

Step-by-step explanation:

Geometric sequence means there is a common ratio. All that means is term divided previous term is the same across your sequence.

ONE WAY:

So we are given here that:

[tex]\frac{f(2)}{f(1)}=\frac{1}{2}[/tex] and that the first term which is [tex]f(1)[/tex] is 2.

[tex]\frac{f(2)}{2}=\frac{1}{2}[/tex]

This implies [tex]f(2)=1[/tex] after multiplying both sides by 2 and getting that [tex]f(2)=\frac{1}{2}(2)=\frac{2}{2}=1[/tex].

So you have that

2,1,...

basically you can just multiply by 1/2 to keep generating more terms of the sequence.

Third term would be [tex]f(3)=1(\frac{1}{2})=\frac{1}{2}[/tex].

Fourth term would be [tex]f(4)=\frac{1}{2}(\frac{1}{2})=\frac{1}{4}[/tex].

...keep doing this til you get to the 10th term.

ANOTHER WAY:

Let's make a formula.

[tex]f(n)=ar^{n-1}[/tex]

[tex]a[/tex] is the first term.

[tex]r[/tex] is the common ratio.

And we want to figure out what happens at [tex]n=10[/tex].

Let's plug in our information we have

[tex]a=2[/tex]

[tex]r=\frac{1}{2}[/tex]:

[tex]f(10)=2(\frac{1}{2})^{10-1}[/tex]

Put into calculator or do by hand...

[tex]f(10)=2(\frac{1}{2})^9[/tex]

[tex]f(10)=2(\frac{1^9}{2^9})[/tex]

[tex]f(10)=2(\frac{1}{2^9})[/tex]

[tex]f(10)=\frac{2}{2^9}[/tex]

[tex]f(10)=\frac{2}{2(2^8)}[/tex]

[tex]f(10)=\frac{1}{2^8}[/tex]

Scratch work:

[tex]2^8=2^5 \cdot 2^3=32 \cdot 8=256[/tex].

End scratch work.

The answer is that the tenth term is [tex]\frac{1}{256}[/tex]

Answer:

For an nth term in a geometric sequence

[tex]U(n) = a ({r})^{n - 1} [/tex]

where n is the number of terms

r is the common ratio

a is the first term

From the question

a = 2

r = 1/2

n = 10

So the 10th term of the sequence is

[tex]U(10) = 2 ({ \frac{1}{2} })^{10 - 1} \\ \\ = 2 ({ \frac{1}{2} })^{9} \\ \\ \\ = \frac{1}{256} [/tex]

Hope this helps you

Answer:

9.392

Step-by-step explanation:

3.1415 + 6.25 = 9.3915

Rounded to the thousandths place, this would be ≈ 9.392

The sum of the given decimal numbers is rounded to the nearest thousandths place as 9.392.

Given that, 3.1415 + 6.25.

Here, sum of the given decimals is 9.3915.

Rounding a number means the process of making a number simpler such that its value remains close to what it was. The result obtained after rounding off a number is less accurate, but easier to use. While rounding a number, we consider the place value of digits in a number.

To round 9.3915 to the nearest thousandths consider the ten thousandths' digit of 9.3915, which is 5. So, the thousandths place value of 9.3915 increase by 1 and ten thousandths place becomes 0.

That, 9.392

Therefore, the sum of the given decimal numbers is rounded to the nearest thousandths place as 9.392.

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Answer:

For 3x^2+4x+4=0

Discriminant= = -32

The solutions are

(-b+√x)/2a= (-2+2√-2)/3

(-b-√x)/2a= (-2-2√-2)/3

For 3x^2+2x+4=0

Discriminant= -44

The solutions

(-b+√x)/2a= (-1+√-11)/3

(-b-√x)/2a= (-1-√-11)/3

For 9x^2-6x+2=0

Discriminant= -36

The solutions

(-b+√x)/2a= (1+√-1)/3

(-b-√x)/2a= (1-√-1)/3

Step-by-step explanation:

Formula for the discriminant = b²-4ac

let the discriminant be = x for the equations

The solution of the equations

= (-b+√x)/2a and = (-b-√x)/2a

For 3x^2+4x+4=0

Discriminant= 4²-4(3)(4)

Discriminant= 16-48

Discriminant= = -32

The solutions

(-b+√x)/2a =( -4+√-32)/6

(-b+√x)/2a= (-4 +4√-2)/6

(-b+√x)/2a= (-2+2√-2)/3

(-b-√x)/2a =( -4-√-32)/6

(-b-√x)/2a= (-4 -4√-2)/6

(-b-√x)/2a= (-2-2√-2)/3

For 3x^2+2x+4=0

Discriminant= 2²-4(3)(4)

Discriminant= 4-48

Discriminant= -44

The solutions

(-b+√x)/2a =( -2+√-44)/6

(-b+√x)/2a= (-2 +2√-11)/6

(-b+√x)/2a= (-1+√-11)/3

(-b-√x)/2a =( -2-√-44)/6

(-b-√x)/2a= (-2 -2√-11)/6

(-b-√x)/2a= (-1-√-11)/3

For 9x^2-6x+2=0

Discriminant= (-6)²-4(9)(2)

Discriminant= 36 -72

Discriminant= -36

The solutions

(-b+√x)/2a =( 6+√-36)/18

(-b+√x)/2a= (6 +6√-1)/18

(-b+√x)/2a= (1+√-1)/3

(-b-√x)/2a =( 6-√-36)/18

(-b-√x)/2a= (6 -6√-1)/18

(-b-√x)/2a= (1-√-1)/3

Answer:

equation: 3x²+4x+4=0 value: -32   solutions: -2±2i√2 / 3

equation: 3x²+2x+4=0 value: -44   solutions: -1±i√11 / 3

equation: 9x²−6x+2=0 value: -36   solutions: 1±i / 3

Answer:

16.78% probability that exactly 12 of them use their smartphones in meetings or classes.

Step-by-step explanation:

For each adult, there are only two possible outcomes. Either they use their smartphone in meetings or classes, or they do not. The probability of a person using their phone in meetings or classes is independent of any other person. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

And p is the probability of X happening.

64​% use them in meetings or classes.

This means that [tex]p = 0.64[/tex]

20 adult smartphone users are randomly​ selected

This means that [tex]n = 20[/tex]

Probability that exactly 12 of them use their smartphones in meetings or classes.

This is P(X = 12).

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 12) = C_{20,12}.(0.64)^{12}.(0.36)^{8} = 0.1678[/tex]

16.78% probability that exactly 12 of them use their smartphones in meetings or classes.

Answer:

Yes

Step-by-step explanation:

b is as in 1b so. . .

2 + 1 = 3

We can plug in b or as "b"

2b + b = 3b

So yes in whatever case 2b + b's value  will always equal 3b's value

Answer:

yes

Step-by-step explanation:

because you can use any number to put for B and they will have the same value as an example we will use 3 for b so 2b = 6 + b = 9 and 3b = 9