Determine the mean and variance of the random variable with the following probability mass function. f(x)=(216/43)(1/6)x, x=1,2,3 Round your answers to three decimal places (e.g. 98.765).

Answers

Answer 1

Mean:

E[X] = ∑ x f(x) = 1 × f (1) + 2 × f (2) + 3 × f (3) = 51/43 ≈ 1.186

Variance:

Recall that for a random variable X, its variance is defined as

Var[X] = E[(X - E[X])²] = E[X ²] - E[X

Now,

E[X ²] = ∑ x ² f(x) = 1² × f (1) + 2² × f (2) + 3² × f (3) = 69/43

Then

Var[X] = 69/43 - (51/43)² = 366/1849 ≈ 0.198

(each sum is taken over x in the set {1, 2, 3})


Related Questions

What is the tangent of 0?

Answers

Answer: Tis 0

Step-by-step explanation:

In parallelogram ABCD, line AC is congruent to line BD. Is ABCD a rectangle?
A. Yes
B. No
C. Cannot be determined

Answers

9514 1404 393

Answer:

  A.  yes

Step-by-step explanation:

The diagonals of a rectangle are congruent and bisect each other.

The diagonals of a parallelogram bisect each other. If they are also congruent, then the parallelogram is a rectangle.

Answer:

Yes.

Step-by-step explanation:

Press option yes

A case of 6 cost 7.5 what it the price per item

Answers

1.25 hope this helps

A bag has 180 balls. the ratio of red to blue to yellow balls is 8:5:7 how many red balls are there and how many blue balls are there

Answers

Answer:

72 red

45 blue

63 yellow

Step-by-step explanation:

8+5+7= 20

180÷20= 9

red = 9*8

blue = 9*5

yellow = 9*7

I am Your Crush boy you have never seen a boy like me if you will see me you will fall in my love. come zom Id- 6622308635 pas- 6UC3yE​

Answers

Answer:

I don't know the answer to ur question. LOL

Answer:

stop being desperate

nobody is gonna fall in love with some desperate weirdo

Using the simple spinner below what is the probability of landing on either 2, 4, or 7?

Answers

Answer:

3/10

Step-by-step explanation:

Total possibilities = 10

favourable possibilities = 3

Answer:

A

Step-by-step explanation:

There is a 1 out of 10 chance that it will land on 2.

There is a 1 out of 10 chance that it will land on 4.

There is a 1 out of 10 chance that it will land on 7.

[tex]\frac{1}{10}\cdot3=\frac{3}{10}[/tex] so the anwser is A.

A canning factory turns out 568 tins of jam on a certain day. How many tins will be produced in 297 working days? ​

Answers

Answer:[tex]568 \: \times \: 297 \: = \: 168696.[/tex]188,696 tins be produced in 297 working days.

Don't forget to thanks Mark as brainlist.

PLEASE HELP
The function in the table is quadratic
True
False

Answers

Answer:

True

Step-by-step explanation:

Each f(x) value increases by 5 so therefore this function would be linear

Hope you understand :)

Domain and function
Function or not a function

Answers

Answer:

Top left: not a function

Top right: not a function

Bottom left: function

Bottom right: not a function

Step-by-step explanation:

A function is a relationship where each x value has it's own y value ( note that domain = x values and range = y values)

For the one on the top left.

S and n have more than one y value.

Because s and n have more than one y value the relation is not a function

For the one of the top right.

There x value "c" has multiple y values therefore the relation is not a function

For the one on the bottom left

Each x value has it's own y value therefore it is a function ( note that the y values can repeat. It's only the x values that can't repeat. )

For the one on the bottom right

The x value "-5" has multiple y values therefore the relation is not a function

How many x-intercepts are in the quadratic equation y = 7x2 − 2x − 1​

Answers

Answer:

There are 2 x intercepts

Which solution finds the value of x in the triangle below?

A right triangle is shown. The hypotenuse has a length of 8. Another side has a length of x. The angle between the hypotenuse and the other side is 60 degrees.

Answers

Answer:

4

Step-by-step explanation:

Since this is a right triangle, and one of the angles measures 60 degrees, we can conclude that the last side measures 30 degrees.

We can see that this is a 30-60-90 degree triangle.

The rules of 30-60-90 degree triangles are that the side opposite the 90 degree angle, or the hypotenuse can be measured with the variable [tex]2a[/tex]. The side opposite the 30 degree angle can be measured with [tex]a[/tex], and the side opposite the 60 degree angle will be measured with [tex]a\sqrt{3}[/tex].

We can see that 8 represents [tex]2a[/tex] because it is the hypotenuse. Since the side marked [tex]x[/tex] is separated by the hypotenuse by an angle of 60 degrees, we note that side marked [tex]x[/tex] is opposite the angle measuring 30 degrees. We note that the side opposite 30 degrees is marked [tex]a[/tex], and since we already know that 8 is equal to [tex]2a[/tex], we realize that the side marked x is equal to [tex]a[/tex], or 4.

The value of x in the triangle is 4.

What is the Pythagorean theorem ?

The square of the length of the hypotenuse of a right triangle equals the sum of the squares of the lengths of the other two sides.

It is given this is a right triangle, and one of the angles measures 60 degrees, we can conclude that the last side measures 30 degrees. By the sum of all the three interior angles of a triangle is 180 degrees

The side opposite the 90 degree angle, or the hypotenuse can be measured with the variable '2a' . The side opposite the 30 degree angle can be measured with 'a' , and the side opposite the 60 degree angle will be measured with 'a√3'.

8 represents '2a' because it is the hypotenuse. Since the side marked x is separated by the hypotenuse by an angle of 60 degrees, we note that side marked x is opposite the angle measuring 30 degrees. We note that the side opposite 30 degrees is marked 'a', and since we already know that 8 is equal to '2a', we realize that the side marked x is equal to

'a' , or 4.

2a=8

a=4

x=a=4

so, the the value of x in the triangle is 4.

Learn more about the  Pythagorean theorem here:

https://brainly.com/question/24154260

#SPJ5

Will give brainliest answer, there has to be two answers to give one of you the brainliest

Answers

Answer:

C

Step-by-step explanation:

[tex] ({8}^{ { - 9})^{ \frac{ - x}{9} } } [/tex]

when putting a power to another power, then these two powers are multiplied.

so, -9 × (-x/9) = (-9 × -x) / 9 = 9x/9 = x

so, this reduces to the original

[tex] {8}^{x} [/tex]

and therefore C is the right answer.


Find the area of the figure below, formed from a triangle and a parallelogram.

144 square millimeters
120 square millimeters
72 square millimeters
96 square millimeters

Answers

total area =A1+A2+A3

A1=1/2b*h

A1=1/2*8mm*6mm

A1=24mmsquare

A2=1/2b*h

A2=1/2*8mm*6mm

A2=24mmsquare

A3=b*h

A3=8mm*6mm

A3=48mmsquare

Atotal=24mmsquare+24mmsquare+48mmsquare

Atotal=96mmsquare

if triangle TAN has vertices T(0, 2), A(-1,3), and N(-2,-4), which of the following coordinates is N' of the dilation from the origin using the scale factor 3?

Answers

Answer:

(-6,-12)

Step-by-step explanation:

A dilation makes a figure gets bigger so just multiply 3 to point N to find N prime.

[tex] - 2 \times 3 = - 6[/tex]

[tex] - 4 \times 3 = - 12[/tex]

So our new coordinates is

(-6,-12)

Answer:

(-6,-12)

Step-by-step explanation:

A dilation makes a figure gets bigger so just multiply 3 to point N to find N prime.

So our new coordinates is

(-6,-12)

Step-by-step explanation:


A boat travels 8 miles north from point A to point B. Then it moves in the direction S 40°W and reaches point Finally, it turns S 40°E and returns to point A
The total distance covered by the boat is______miles

A. 14.95
B. 18.44
C. 20.04
D. 25.88

Answers

Answer:

B.18. 44 miles

Step-by-step explanation:

We are given that

Distance between A and B=8 miles

Angle B=Angle BCQ=40 degree (Alternate interior angles)

Angle ACB=180-Angle ACP-Angle BCQ

Angle ACB=180-40-40=100 degree

In triangle ABC

Angle A+ Angle B +Angle C=180 degree using sum of angles of triangle property

Substitute the values

[tex]\angle A+40+100=180[/tex]

[tex]\angle A+140=180[/tex]

[tex]\angle A=180-140[/tex]

[tex]\angle A=40[/tex] degree

Angle A=Angle B

When two angles are equal of a triangle then the triangle is isosceles triangle.

Therefore, triangle ABC is an isosceles triangle.

[tex]\implies BC=AC [/tex]

Now, Sine law

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

Using the sine law

[tex]\frac{BC}{sin 40}=\frac{AB}{sin 100}[/tex]

[tex]\frac{BC}{sin 40}=\frac{8}{sin 100}[/tex]

[tex]BC=\frac{8\times sin40}{sin 100}[/tex]

BC=5.22

AC=BC=5.22 miles

Now, total distance covered by the boat=AB+BC+AC

Total distance covered by the boat=8+5.22+5.22=18.44 miles

Hence, option B is correct.

determine the 2nd and 3rd terms of a geometric sequence of which T1 =5 and T4=40​

Answers

Answer:

Second term of this sequence: [tex]10[/tex].

Third term of this sequence: [tex]20[/tex].

Step-by-step explanation:

The first step is to find the common ratio of this sequence.

In a geometric sequence, multiply one term by the common ratio to find an expression for the next term. Let [tex]r[/tex] denote the common ratio of this sequence. For this sequence:

The first term of this sequence is [tex]5[/tex]. Multiply the first term by the common ratio to find an expression for the third term: [tex]5\, r[/tex].Multiply the second term by the common ratio to find an expression for the fourth term: [tex]5\, r^{2}[/tex].Similarly, an expression for the the fourth term would be: [tex]5\, r^{3}[/tex].

However, the question states that the value of the fourth term is [tex]40[/tex]. In other words, [tex]5\, r^{3} = 40[/tex].

Solve this equation for [tex]r[/tex]:

[tex]r^{3} = 8[/tex].

[tex]r = 2[/tex].

(Since the power of [tex]r[/tex] is non-even in the equation, there's no need to consider the sign of [tex]r\![/tex] when taking the cube root.)

Substitute [tex]r = 2[/tex] into the expression for the second term and the third term to find their values:

Second term: [tex]5\, r = 10[/tex].Third term: [tex]5\, r^{2} = 20[/tex].

Which of the following expressions has a Value of 6.18???

Answers

Answer:

B. -21.012÷ -3.4

its yr correct ans.

hope it helps

stay safe healthy and happy.
B) -21.012/-3.4= 6.18

Of the at-home games, what proportion of games were wins? (Note: Some answers are rounded to two decimal places

Answers

Answer:

0.33

Step-by-step explanation:

See comment for complete question

Given

[tex]H = 60\%[/tex]

[tex]W=25\%[/tex]

[tex]HW = 20\%[/tex] --- at-home wins

Required

The proportion of at-home games that were wins

This proportion is represented as:

[tex]Pr = HW : H[/tex]

Substitute values for HW and H

[tex]Pr = 20\% : 60\%[/tex]

Divide by 20%

[tex]Pr = 1 : 3[/tex]

Express as fraction

[tex]Pr = 1 /3[/tex]

[tex]Pr = 0.33[/tex]

please answer

Find the area of the polygon.

6 cm6 cm10 cm

Answers

Answer:

Area: 360 cm

Perimeter: 44 cm

Step-by-step explanation:

To calculate the area, you must multiply the length x width.

If you need help calculating the perimeter too, just add all your lengths and widths together twice.

Bindi is buying pet food with a coupon for 20% off. The original price of the bag of food is $39.
Which answer gives the best estimate for the price after the discount?

$48
$19
$34
$32

Answers

I think its $32.
.20 x 39 = 7.8
39 - 7.8 = $31.2

Please help me i will give Brainly

Answers

Answer:

Step-by-step explanation:

[tex]\frac{3x + 5}{2x + 7}[/tex] = 5

do cross multiplication

3x + 5 = 5(2x + 7)

3x + 5 = 10x + 35

5 - 35 = 10x - 3x

-30 = 7x

-30/7 = x

20 A

since there are 7 angles given it means that the polygon is heptagon as heptagon has 7 sides.

sum of interior angle of heptagon = (n-2)*180

(7-2)*180

5*180

900

Now ,

110 + 90 + 150 + 102 + 110 + 170 + x = 900

732 + x = 900

x = 900 - 732

x = 168 degree

20 B

since 5 angles are given it means that the polygon is pentagon as pentagon has 5 sides.

sum of interior angles of a pentagon = (n-2)*180

(5-2)*180

3*180

540 degree

Now ,

110 + 95 + 120 + 114 + x = 540

465 + x = 540

x = 540 - 465

x = 75 degree

21

let one rational number be x

according to the question,

1/7 * x = 2

x/7 = 2

do cross multiplication

x = 14

The accompanying data are lengths (inches) of bears. Find the percentile corresponding to 61.0 in.
(Round to the nearest whole number as needed.)
Bear Lengths
36.0 37.0 39.5 40.0 40.5 43.0 44.0 45.5 45.5 46.5 48.0 48.00 49.0 50.0 51.5 52.5 53.0 53.5 54.0 57.3 57.5 58.0 58.5 59.0 59.5 60.0 61.0 61.0 61.0 61.5 62.0 62.5 63.0 63.0 63.5 64.0 64.0 64.0 64.5 65.0 66.0 67.5 67.5 68.5 70.0 70.5 71.5 72.0 72.5 72.5 72.5 73.5 74.5 77.5

Answers

Answer:

52nd percentile

Step-by-step explanation:

The sorted data :

36.0, 37.0, 39.5, 40.0, 40.5, 43.0, 44.0, 45.5, 45.5, 46.5, 48.0, 48.00, 49.0, 50.0, 51.5, 52.5, 53.0, 53.5, 54.0, 57.3, 57.5, 58.0, 58.5, 59.0, 59.5, 60.0, 61.0, 61.0, 61.0, 61.5, 62.0, 62.5, 63.0, 63.0, 63.5, 64.0, 64.0, 64.0, 64.5, 65.0, 66.0, 67.5, 67.5, 68.5, 70.0, 70.5, 71.5, 72.0, 72.5, 72.5, 72.5, 73.5, 74.5, 77.5

The total size of the data = 54

The value 61.0 occurs in position ; 27th, 28th and 29th

Taking the position average :

(27+28+29)/3 = 84/3 = 28th position

This means the percentile score of 61 is :

(Position average / total size) * 100%

(28/54) * 100%

0.5185185 * 100%

= 51.85%

This means that 61 inch length falls in the 52nd percentile

I need help with question 9

Answers

9514 1404 393

Answer:

  a) yes

  b) see attached

  c) see discussion

  d) neither

  e) increasing (2,5); decreasing (-2, 2)

Step-by-step explanation:

a) The graph passes the vertical line test, so is the graph of a function.

__

b) A table of values is attached

__

c) Generally, this sort of function would be defined piecewise:

  [tex]\displaystyle f(x)=\begin{cases}-\dfrac{1}{2}x+1&\text{for }-2\le x<2\\2x-4&\text{for }2\le x \le5\end{cases}[/tex]

In the attachment, we have shown the use of the "maximum" function to define it. The effect is the same.

__

d) The function has no symmetry about the origin or the y-axis, so is neither odd nor even.

__

e) The function is increasing where the line has positive slope, on the interval (2, 5). The function is decreasing where the line has negative slope, on the interval (-2, 2).

A.109
B.87
C.98
D.69

Answers

Answer:

hey what's

Step-by-step explanation:

a question wow okay the answer is

I think it’s b because the other ones are different

Calculate the number of ways to form a set of three distinct items such that no two of the selected items are in the same row or same column

Answers

Answer:

1200

Explanation:

Order does not matter, if we said xyz order, it would still not make a difference if it was zyx or yzx hence we use the combination formula:

nCr = n! / r! * (n - r)!

where n= total number of items

r= number of items chosen at a time

Combinations are used when the order of events do not matter in calculating the outcome.

We calculate using the formula:

(30×20×12)÷3!=1200

There are therefore 1200 ways for the three distinct items to not be in same row or column

If Joanne can paint a room in 3 hours and her sister Angela can paint the same room in 4 hours, how long (in h) would it take Joanne and Angela to paint the room working together? Round to the nearest tenth.

Answers

Answer:

Step-by-step explanation:

If J can paint a room in 3 hours, in 1 hour she gets [tex]\frac{1}{3}[/tex] of the job done.

If A can paint a room in 4 hours, in 1 hour she gets [tex]\frac{1}{4}[/tex] of the job done. We need to find out how long it takes them if they paint together. The equation for this is:

[tex]\frac{1}{3}+\frac{1}{4}=\frac{1}{x}[/tex] where x is the number of hours it takes them to get the job done together. Multiply everything through by 12x to get

4x + 3x = 12 so

7x = 12 and

x = 1.7 hours to get the room painted together.

what term can you add to
[tex] \frac{5}{6} x - 4[/tex]
to make it equivalent to
[tex] \frac{1}{2} x - 4[/tex]

Answers

9514 1404 393

Answer:

  -1/3x

Step-by-step explanation:

We want to find the term 'a' such that ...

  (5/6x -4) + a = (1/2x -4)

Add 4-1/2x to both sides.

  (5/6 -1/2)x -4 +4 +a = 0

  (5/6 -3/6)x + a = 0 . . . . . . express the fractions using a common denominator

  1/3x + a = 0 . . . . . . . . . . simplify the difference

  a = -1/3x . . . . . . . . . . .subtract 1/3x

The term you can add to make the desired equivalent is -1/3x.

equivalent fraction of 9/11​

Answers

Answer:

1822

Step-by-step explanation:

The fraction 1822 is equal to 911 when reduced to lowest terms.

18

22

is equivalent to 9

11

because 9 x 2 = 18 and 11 x 2 = 22

27

33

is equivalent to 9

11

because 9 x 3 = 27 and 11 x 3 = 33

36

44

is equivalent to 9

11

because 9 x 4 = 36 and 11 x 4 = 44

Answer:

18/22

Step-by-step explanation:

You can choose any number and if you multiply the top number (numerator) and the bottom number (denominator) by that same number, the fractions are equivalent.

If you choose the number 2, then multiply 9 x 2 = 18, and 11 x 2 = 22

Or multiply by 7. Then you would get an equivalent fraction of 63/77  

Suppose X has a normal distribution with mean 10.0 and standard deviation 5.0 what is the P(2.0

Answers

Answer:

what r u answers picks

Step-by-step explanation:

cant answer with out of t

Which of the following is a polynomial
A. 1-5x^2/x
b. 11x
c. 2x^2- square root x
d. 3x^2+6x

Answers

Answer:

 B and D are polynomial

Step-by-step explanation:

An algebraic expression with non-zero coefficients and variables having non-negative integers as exponents is called a polynomial.

A)

If it is [tex]1 -\frac{5x^{2}}{x }=1-5x[/tex]   , then it is a polynomial.

But if it is [tex]\frac{1-5x^{2}}{x}[/tex] then it is not a polynomial

Other Questions
Bonita Industries purchased machinery for $1030000 on January 1, 2017. Straight-line depreciation has been recorded based on a $82000 salvage value and a 5-year useful life. The machinery was sold on May 1, 2021 at a gain of $27500. How much cash did Bonita receive from the sale of the machinery?a. $138,000 b. $162,000 c. $198,000 d. $258,000 PLEASE HELPFill in the blanks. Then, choose the property of addition you used.(a)3+_= 3(Choose one)(b)4 + 7) + _1 = 4 + (7 + 3)(Choose one)(c)9+8 = 8+_(Choose one)Fill in the blank and choose a property Can someone please answer this? Sticky buns sell for $1.25 each,or $10.89 per dozen. how much does each bun cost if purchased by the dozen? How much do you save on 12 sticky buns? A 46.6-mgmg sample of boron reacts with oxygen to form 150 mgmg of the compound boron oxide. Part A What is the empirical formula of boron oxide Mo will receive a perpetuity of $27,000 per year forever, while Curly will receive the same annual payment for the next 40 years. If the interest rate is 7.1 percent, how much more are Mo's payments worth can somebody help me Read the excerpt from "Tools of the Spymaster."James Jay's invisible ink did not become visible by heating. As he described it, his ink "would elude the generally known means of detection, and yet could be rendered visible by a suitable counterpart." Jay's invisible ink consisted of two chemicals. An agent used one chemical to write an invisible message. To read the message, the reader had to brush a second chemical on the paper; that chemical made the message visible. The two-bottle system, supplied by Jay, gave Washington the secure form of writing that he wanted.Which statement best expresses the central idea of the excerpt?James Jay was a spy for the Americans and had knowledge of chemistry.James Jays system required two chemicals for writing and reading invisible ink messages.James Jay believed secret messages that became visible because of heat were not secure.James Jays invisible ink system allowed Washington to read secret messages. Xavier is testing different types of planting soil to determine which type is most effective in growing blueberry bushes. He purchases two different brands of planting soil from a local store. Xavier applies Brand A to an area of the yard that receives full sunlight and Brand B to another area of the yard that is in partial sunlight. He waters the area with Brand B daily; he waters the area with Brand A every other day. At the end of the study, Xavier concludes Brand A is more effective in growing blueberry bushes. Why is his conclusion not valid? The volume of a cube is 2,744 m3. What is the side length of the cube? Help and explain !!! 2a is five times bigger than B. Circle the ratio a:b.A. 10:1B. 1:10C. 5:2D. 2:5 Use the zero product property to find the solutions to the equation x2 + 12 = 7x.x = 4 or x = 3x = 4 or x = 3x = 3 or x = 4x = 3 or x = 4 MC Qu. 117 Cosi Company uses a job order costing... Cosi Company uses a job order costing system and allocates its overhead on the basis of direct labor costs. Cosi expects to incur $830,000 of overhead during the next period, and expects to use 53,000 labor hours at a cost of $10.00 per hour. What is Cosi Company's overhead application rate The first law of thermodynamics defines chemical energy. defines entropy. is a statement of conservation of energy. provides a criterion for the spontaneity of a reaction. Please answer i need help please i will give you brainlest please The product of 2 integers is 72. One number is two less than five times the other. Which equation can be used? The main outputs of which process are a quality management plan, quality metrics, project management plan updates, and project documents updates? which organsism transform nitrogen to a form this useful to plants? a. bacteria b.animals c.fungi d.humans The primary advantage of hexadecimal notation, compared with binary notation, is its ____________________.