Let XX be a random variable that is equal to the number of heads in two flips of a fair coin. What is \text E[X^2]E[X 2 ]

Answers

Answer 1

Answer:

Step-by-step explanation:

From the given information, it is likely that the random variable(X) have the values below:

Let head be H

Let tail be T

So;

X(HH) = 2;

X(HT) = 1;

X(TH) = 1;

X(TT) = 0

The distribution can now be computed as:

[tex]p(X= TT) = \dfrac{1}{4}[/tex]

[tex]p(X=TH) = \dfrac{1}{4}[/tex]

[tex]p(X=HT) = \dfrac{1}{4}[/tex]

[tex]p(X=HH)= \dfrac{1}{4}[/tex]

Now, the expected value that is equivalent to the number of heads when the coin is flipped twice is:

[tex]E(X) = p(TT)*X(TT)+p(TH)*X(TH)+p(HT)*X(HT)+p(HH)*X(HH)[/tex]

[tex]E(X) = \dfrac{1}{4}\times 0 + \dfrac{1}{4}\times 1 + \dfrac{1}{4}\times 1 + \dfrac{1}{4}\times 2[/tex]

[tex]E(X) = 0 + \dfrac{1}{4}+ \dfrac{1}{4} + \dfrac{1}{2}[/tex]

[tex]E(X) =\dfrac{1+1+2}{4}[/tex]

[tex]E(X) =\dfrac{4}{4}[/tex]

E(X) = 1

[tex]E(X^2) = p(TT)*X(TT)^2+p(TH)*X(TH)^2+p(HT)*X(HT)^2+p(HH)*X(HH)^2[/tex]

[tex]E(X^2) = \dfrac{1}{4}\times 0^2+ \dfrac{1}{4}\times 1^2 + \dfrac{1}{4}\times 1^2 + \dfrac{1}{4}\times 2^2[/tex]

[tex]E(X^2) = 0 + \dfrac{1}{4}+ \dfrac{1}{4} + \dfrac{4}{4}[/tex]

[tex]E(X^2) =\dfrac{1+1+4}{4}[/tex]

[tex]E(X^2) =\dfrac{6}{4}[/tex]

[tex]E(X^2) =1.5[/tex]

Finally; To compute E²[X]

E²[X] = E[X]²

E²[X] = 1²

E²[X] = 1


Related Questions

I neeed the answer plssss

Answers

Answer:

300km

Step-by-step explanation:

if 1 hr=80

then take 80 and multiply it by 3.75

hope this helps!

please give brainiest if you want<3

Answer:

300km

Step-by-step explanation:

I would appreciate if someone could answer this

Answers

Answer:

x = 15

LN and MO both equal 43

Step-by-step explanation:

LN and MO are diagonals in rectangle

Diagonals of a rectangle are congruent Hence, 4x - 17 = 2x + 13

Now we solve for x

4x - 17 = 2x + 13

Add 17 to both sides

4x = 2x + 30

Subtract 2x from both sides

2x = 30

Divide both sides by 2

x = 15

Now we want to find the values of LN and MO

To do so we substitute 15 for x in it's given expression ( note: because LN = MO we only need to do this process once )

LN = 4x - 17

Substitute 15 for x

4(15) - 17

Multiply

60 - 17

Subtract

LN and MO = 43

If using the method of completing the square to solve the quadratic equation
x^2 + 8x – 4 = 0, which number would have to be added to "complete the square"?

Answers

Step-by-step explanation:

everything can be found in the picture

Jordan is going to a friends birthday party. He couldn’t decide if he should wear a coat so he checked the weather. The weather report showed it would be -11 degrees in the morning but by the afternoon there would be a drastic increase of 73 degrees. Write an equation that represents this situation. Then find the temperature in the afternoon.
plz reply within five minutes and plz give an explanation on your process and how did you approach your problem and ofc loving the question.

Answers

Answer:

-11 + 73

62°

Step-by-step explanation:

Morning temperature = - 11

Afternoon temperature = morning temperature + 73°

We obtain the temperature in the afternoon by adding the 73° increase in temperature temperature the morning temperature ;

Hence, temperature in the afternoon will be :

-11° + 73° = 62°

Hence, after oon temperature will be 62°

In general, half of all the customers you speak to will ask about any upcoming pricing discounts or promotions. Of those who do ask, only 20% qualify for the discount. So that means if I speak to 300 customers, how many will qualify for the discount

Answers

Answer:60

Step-by-step explanation:

300 of 20% is 60

The number of qualified customers for the discount will be 60.

What is the percentage?

The Percentage is defined as representing any number with respect to 100. It is denoted by the sign %. The percentage stands for "out of 100." Imagine any measurement or object being divided into 100 equal bits.

It is given that half of all the customers you speak to will ask about any upcoming pricing discounts or promotions. Of those who do ask, only 20% qualify for the discount. So that means if I speak to 300 customers.

The number of qualified customers will be calculated as below:-

The qualified customers are 20% of 300.

Number = 300 x (20/100)

Number = 300 x 0.2

Multiply the number 330 with 0.2 to get the final value.

Number = 60

Therefore, the number of qualified customers for the discount will be 60.

To know more about percentages follow

https://brainly.com/question/24304697

#SPJ2

The rate to rent a small moving van is $30 per day, plus $2 per mile. Jada rented a van to drive to her new home. It took
two days, and the total cost was $360. How many miles did she drive?

Answers

150 miles cause 150 x 2 is 300 plus the $30 a day fee

A hotel spent $504 on new hair dryers. The hair dryers cost $8 each. The hotel has 6 floors with the same number of rooms on each floor. If every room gets a new hair dryer, how many hair dryers will be left over?

Answers

Answer:

504/8=63/6=10.5

10 rooms per floor with 3 leftover

A large university chemistry course has a required textbook available for $ 154 and a recommended supplement for $ 36. The university bookstore finds, over time, that 15% of students enrolled in the course purchase only the textbook, while 75% buy both the textbook and the supplement. No students buy only the supplement. a) What percent of students buy neither the textbook nor the supplement from the bookstore

Answers

Answer:

10% of students buy neither the textbook nor the supplement from the bookstore

Step-by-step explanation:

We have that:

15% buy only the textbook.

75% buy both the textbook and the supplement.

None buy only the supplement.

a) What percent of students buy neither the textbook nor the supplement from the bookstore

15% + 75% = 90% buy at least one of them. So

100% - 90% = 10% buy neither.

A grocery store chain uses loyalty cards that offer discounts on sale attheir store. The probability that a randomly chosen shopper has a loyaltycard is 0.8. A group of shoppers have been selected at random to completea customer satisfaction survey. Let Xi be a random variable that equals 1 when a customer has a loyalty card and 0 otherwise.

Required:
a. Construct a joint probability table for the random variables X, and X.
b. Define the event that the first four customers sampled have loyalty cards in terms of the random variables X, X2, X3, and Xd. Then compute the probability of this event.

Answers

The answer is a cause

The club with an occupancy of 100 will sell out at $25 per ticket. If the owner decides to increase the price by $5, then 2 less tickets will be sold. Determine the revenue function if x is the number of $5 increases.

Answers

Answer:

100 + (5X) = -2X

Step-by-step explanation:

Since the club with an occupancy of 100 will sell out at $ 25 per ticket, and if the owner decides to increase the price by $ 5, then 2 less tickets will be sold, to determine the revenue function if X is the number of $ 5 increases the following calculation must be performed:

100 + (5X) = -2X

So, for example, if the price were increased by $ 15, the equation would apply as follows:

15/5 = 3

100 + (5x3) = -2 x 3

100 + 15 = -6

115 = -6

Which expression is equivalent to 5^15 x 5^5

Answers

Answer:

[tex]5^{15} * 5^{5}[/tex]

= [tex]25^{20\\}[/tex]

Triangle ABC IS dilated using the origin as the center of dllation to create triangle A'B'C'. What rule best represents the dilation applied to triangle ABC to ​

Answers

The scale factor is 3 so B would be your answer because all coordinates are multiplied by 3

Use slopes and y-intercepts to determine if the lines y=−2/3x+2 and −3x+2y=−4 are parallel.

Answers

Answer:

the answer is no

Step-by-step explanation:

y = -2/3x+2

2y = 3y-4

y = 3/2y-2

but here's a comment: it is perpendicular because it is it's opposite reciprocol

Select the correct answer.
Which expression is equivalent to the glven expression?
(3m-4)^3(3m^5)
A. 81/m^2 B.27/m^7 C. 27/m^2 D.81/m^7

Answers

The answer for this question is D

The correct expression which is equivalent to the given expression is,

⇒ 81 / m⁷

What is an expression?

Mathematical expression is defined as the collection of the numbers variables and functions by using operations like addition, subtraction, multiplication, and division.

Given that;

The expression is,

⇒ (3m⁻⁴)³ (3m⁵)

Now, We can simplify as;

⇒ (3m⁻⁴)³ (3m⁵)

⇒ (3³m⁻¹²) (3m⁵)

⇒ (27m⁻¹²) (3m⁵)

⇒ 81 m⁻¹²⁺⁵

⇒ 81 m⁻⁷

⇒ 81 / m⁷

Thus, The correct expression which is equivalent to the given expression is,

⇒ 81 / m⁷

Learn more about the mathematical expression visit:

brainly.com/question/1859113

#SPJ7

What is the value of y in the equation 3y - 8 = 22?
7.3
8
10
14

Answers

The answer to your question is ten

Simplify the fraction to lowest terms.
56/
182

Answers

the answer to your question is 4/13.

Social scientists discovered that 1,013 General Social Survey (GSS) respondents in 2010 watched television for an average of 3.01 hours per day, with a standard deviation of 2.65 hours per day. Answer the following questions, assuming the distribution of the number of television hours is normal.

Required:
a. What is the Z score for a person who watches more than 8 hr/day?
b. What proportion of people watch television less than 5 hr/day? How many does this correspond to in the sample?
c. What number of television hours per day corresponds to a Z score of +1?
d. What is the percentage of people who watch between 1 and 6 hr television per day?

Answers

Answer:

Following are the responses to the given question:

Step-by-step explanation:

[tex]Sample \ size = n = 1013\\\\\mu = 3.01\\\\\sigma = 2.65[/tex]

For point a:

Using formula:

[tex]Z = \frac{(X - \mu)}{\sigma}\\\\X = 8\\\\Z = \frac{(8- 3.01)}{2.65} = 1.88\\\\[/tex]

For point b:

[tex]P(X<5)=?\\\\ x = 5\\\\ Z = \frac{(X - \mu)}{\sigma} = \frac{(5 -3.01)}{2.65} = 0.7509434\\\\P(Z< 0.7509434) = 0.7736566\\\\P(X<5) = P(Z< 0.7509434) = 0.7736566[/tex]

For point c:

[tex]X=? \\\\Z = 1\\\\\text{Formula for X score:}\\\\X = \mu + Z \times \alpha\\\\X = 3.01 + 1\times 2.65 = 3.01 + 2.65 = 5.66[/tex]

For point d:

[tex]P(1 \leq X \leq 6)=? \\\\P(1 \leq X \leq 6) = P(X \leq 6) - P(X\leq 1) = P(X< 6) - P(X<1)\\\\\text{Z score for x} = 6\\\\Z = \frac{(6 - 3.01)}{2.65} = 1.128301887 \\\\P(Z< 1.128301887) = 0.870403777 \\\\P(X<6) = P(Z< 1.128301887) = 0.870403777 \\\\\text{Z score for x} = 1 \\\\[/tex]

[tex]Z = \frac{(1 -3.01)}{2.65} = -0.758490566\\\\P(Z< -0.758490566) = 0.224078679\\\\P(X<1) = P(Z< -0.758490566) = 0.224078679 \\\\P(1 \leq X \leq 6) = P(X \leq 6) - P(X\leq 1) = P(X<6) - P(X<1) \\\\ = 0.870403777 - 0.224078679 = 0.646325097 \\\\\text{Required probability} = 0.646325097[/tex]

Really struggling with this, can someone please help me out and give me a brief explanation?

Answers

Answer:

the answer is 220

Step-by-step explanation:

the formula for surface area of a rectangular prism is A=2(wl+hl+hw)

w = width

h= height

l = length

and when you have those lengths, you have to substitute.

What is the distance between the two points? (-18, -6) & (-18,-1)

A. 4
B. 5
C.6
D. 7

Answers

Answer:

5

Step-by-step explanation:

D² = ( x2 - x1 )² + ( y2 - y1 )²

= [ (-18) - (-18) ]² + [ (-1) - (-6) ]²

= ( -1 + 6 )²

D² = ( 5 )²

hence, D = 5

Answer: B) 5

Step-by-step explanation:

Let's start by finding the distance from one x coordinate to the other. Remember subtracting by a negative is the same as adding a positive

-18-(-18)

-18+18

0

There is no distance away from the x value so the distance we need to count is from the y value

-1-(-6)

-1+6

5

The distance between the two points is 5.

Solve the compound inequality

Answers

Answer:

B

Step-by-step explanation:

Answer:

I'm  so sorry I did not mean to answer! Ignore my response

Step-by-step explanation:

Which scenario is modeled by the equation (x) (0.6) = 86 dollars and 46 cents?

Answers

Answer: (C)A picnic table is on sale for 60 percent off. The original price of the picnic table is x, $144.10.

Answer:

Answer: (C)A picnic table is on sale for 60 percent off.

Step-by-step explanation:

well someone copied me but okay :[

Write an equivalent expression for: 5(5x - 9) *

Answers

Answer:

25x - 45

Step-by-step explanation:

5(5x - 9)

Distribute

5*5x - 5* (9)

25x - 45

Answer:

➛ 25 x - 45

Step-by-step explanation:

➛ 5 ( 5 x - 9 )

Using distributive property multiply both by 5

➛ 5 × 5 x - 5 × -9

➛ 25 x - 45

I need this by to night somebody help pls

Answers

Answer:

0° < x < 83.76°

Step-by-step explanation:

Assuming a pyramid with a square base, and the height of the pyramid varies from almost zero to almost infinity.

The largest value for the angle x+2 is when the height of the pyramid is almost zero.

Then the face is an isosceles triangle with base 13 and height 14.

The angle opposite the base is then

x+2  = 2*atan(6.5/7) = 2* 42.879 = 85.76°

when the height is almost infinite, the angle is almost zero.

Therefore the range of the value of x

0° < x < 83.76°

plz it's do to day HELP PLZ​

Answers

Answer:

9 units^3

Step-by-step explanation:

V = l*w*h

   = 1 1/2 * 4 * 1 1/2

Change to improper fractions

  = 3/2 * 4 * 3/2

   = 36/4

   = 9 units^3

Let the sequence be 1, 3, 5, 7, 9……… then this sequence is

Answers

the answer is 11 because 2 multiple are increasing

Answer:

An arithmetic sequence, The difference in any term with the previous term is same.

Step-by-step explanation:

See, ah this is a little bit easy question so let’s start solving it -:

Firstly, um see the difference between the given numbers-: 1, 3, 5, 7,9 _?

Between 1 and 3 the difference is 2

Between 5 and 3 the difference is 2

Between 7 and 5 the difference is 2

Between 9 and 7 the difference is 2

So, here we see the difference among all is same. So. it is an arithmetic sequence.

So, let's   find the fourth term. We can either do it by arithmetic progression or  by simply adding 2 to 7. I.ll first show you by doing A.P. then we will check the answer by adding 2 to 7.

So, as we know the basic formula of A.P. which is -: a1+(n-1)d

Here, a1=1, n=5, d=2

Let’s put the values in the formula-: 1+(5–1)2 = 1+(4)2 = 1+8 = 9

Now let’s check it. As the difference between each digit is same so definately the difference between 9 and the unknown number is 2.

Then, the unknown no. is 9+2 = 11

Hence, the answer is 11

The value of x for which the expressions 5(3x-4) equal to 2(2x+1)

Answers

Answer:

the value of x is 2.

Step-by-step explanation:

5(3x - 4) = 2(2x + 1)

15x - 20 = 4x + 2

15x - 4x = 2 + 20

11x = 22

x = 22/11

x = 2

Which of the coordinate pairs below are separated by a horizontal distance of greater than 11 units? Select all that apply.
A) (-6.4, 5.1) and (5.5, 5.1)
B) (4.7, -5.5) and (-3.3, -5.5)
C) (11/3, 4) and (−10/3, 4)
D) (-12, 5) and (2, 5)

Answers

9514 1404 393

Answer:

   A, D

Step-by-step explanation:

The horizontal distance between the points is the difference of their x-coordinates.

A) 5.5 -(-6.5) = 12.0 . . . greater than 11

B) 4.7 -(-3.3) = 8.0

C) 11/3 -(-10/3) = 21/3 = 7

D) 2 -(-12) = 14 . . . greater than 11

Solve for x: 12x+5=3x+35

Answers

Answer:

The answer would be 3.33.

Step-by-step explanation:

Simplifying 12x + 5 = 3x + 35

Reorder the terms: 5 + 12x = 3x + 35

Reorder the terms: 5 + 12x = 35 + 3x

Solving 5 + 12x = 35 + 3x

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-3x' to each side of the equation. 5 + 12x + -3x = 35 + 3x + -3x

Combine like terms: 12x + -3x = 9x 5 + 9x = 35 + 3x + -3x

Combine like terms: 3x + -3x = 0 5 + 9x = 35 + 0 5 + 9x = 35

Add '-5' to each side of the equation. 5 + -5 + 9x = 35 + -5

Combine like terms: 5 + -5 = 0 0 + 9x = 35 + -5 9x = 35 + -5

Combine like terms: 35 + -5 = 30 9x = 30

Divide each side by '9'. x = 3.333333333

Simplifying x = 3.333333333

Please answer this, I am confused (5^2)(7^2)(3^2)

Answers

Given:

The expression is:

[tex](5^2)(7^2)(3^2)[/tex]

To find:

The value of the given expression.

Solution:

We have,

[tex](5^2)(7^2)(3^2)[/tex]

On simplification, we get

[tex](5^2)(7^2)(3^2)=(25)(49)(9)[/tex]

[tex](5^2)(7^2)(3^2)=11025[/tex]

Therefore, the value of the given expression is 11025.

I would really appreciate if someone could answer this:)

Answers

Answer:

first you need to know that the the sum of the co-interior angle is  180 degree and the sum of the opposite side of  parallelogram is always equal.

now x+140=180(being co - interior angle)

or, x= 180-140

therefore, x =40 degree

y= 140 degree because sum of the opposite side of  parallelogram is always equal.

x= z=40 degree (sum of the opposite side of  parallelogram is always equal.

when you are again confused go in this link

 ----> https://www.scholr.com/ncert-solutions/consider-the-following-parallelograms-fi/40087/

plz mark me brainliest + thanks

Other Questions
Definicin de imperialismo help me find the answer Ariel has a plastic ice cream cone in her food playset. The ice cream cone is a half-sphere sitting on top of a cone. What is theapproximate volume of the toy ice cream cone? Use 3.14 for x. While some people play basketball professionally. Millions play basketball for fun.Which version of the sentence best emphasizes the subject?A. While some people play basketball professionally and millions play basketball for fun.B. While some people play basketball professionally, millions play basketball for fun.C. While some people play basketball professionally; Millions play basketball for fun.D. While some people play basketball professionally, but millions play basketball for fun. Five athletes are in a 100k race. How many different ways can they finish based on their order? The Titanus beetle can measure 16710 centimeters in length, and the Giant Weta beetle can measure 8510 centimeters in length. How much longer is the Titanus than the Giant Weta? ratios that are equivalent to 7/6 How did the scientific revolution affect societies between the 17th and 19thcenturies? what is a example of clauses Which expression represents the length, in inches,of the framed picture? Complete each of the following sentences by selecting the correct option from the dropdown menu.While there were relatively few educational opportunities for people in antebellum Mississippi, the had the most educational options. Sons of wealthy planters were generally educated at . On the other hand had virtually no access to formal education in the state. were legally barred from learning to read and write. Select the adverb phrase to complete the sentence sanj napped on the chair What is the original price of an item cost if the tax is 9.25% and the discount is 25% and the new price after discount and tax is $62.28? Find an expression which represents the difference when (-4x 3y) is subtractedfrom (-2x 10y) in simplest terms. A firm has an equity multiplier of 1.57, an unlevered cost of equity of 14 percent, a levered cost of equity of 15.6 percent, and a tax rate of 21 percent. What is the cost of debt Una pelota q rodaba a 93,6 dm/s, luego de 14,4 segundos se detiene.cual fue el valor de su aceleracion? Select the correct answer from each drop-down menu.The pancreas is an accessory organ whose function aids the chemical digestion of food.If the pancreas fails to make, it will inhibit the action of enzymes and affect chemical digestion. Also, might damage the small intestine walls. Two 2 kg masses is placed at either end of a rod that has a mass of .5 kg and a length of 3 m. What is the moment of inertia if the system it is rotated about (a) one end of the rod and (b) the center of the rod? A hiker is standing 40 feet away from a tree that is 50 feet tall. What is the angle of elevation from the hikers foot to the top of the tree??HELP ME PLEASE ITS URGENT Elvis has asked Bonnie out of a date to a baseball game. Elvis is a friend of Bonnies classmate Ginger and she has met him a few times before. She wants to go to the baseball game but is concerned for her safety.What should Bonnie do before going out to best ensure her safety?