The random variable X has the following probability mass function.

X -1 0 2 6 7
P(x) 0.3 0.1 0.3 0.2 0.1

Required:
a. Find the probability P( -1 < X ≤ 2) = ______
b. Find the cumulative distribution function F(x) and calculate F(3.2) = _____________
c. E(X) = ___________
d. Var(X) = __________
e. Suppose the number of errors in a piece of software has a Poisson distribution with parameter λ=3. The probability that there are 5 errors in a piece of software is ____.

Answers

Answer 1

Given the PMF

[tex]P(X=x) = \begin{cases} 0.3 & \text{if } x \in \{-1, 2\} \\ 0.1 & \text{if } x \in \{0, 7\} \\ 0.2 & \text{if } x = 6 \\ 0 & \text{otherwise} \end{cases}[/tex]

(a)

[tex]P(-1 < X \le 2) = P(X = 0) + P(X = 2) = 0.1 + 0.3 = \boxed{0.4}[/tex]

(b) The CDF is defined as [tex]F_X(x) = P(X \le x)[/tex], so that

[tex]F_X(x) = \begin{cases} 0 & \text{if } x < -1 \\ 0.3 & \text{if } -1 \le x < 0 \\ 0.4 & \text{if } 0 \le x < 2 \\ 0.7 & \text{if } 2 \le x < 6 \\ 0.9 & \text{if } 6 \le x < 7 \\ 1 & \text{if } x \ge 7 \end{cases}[/tex]

It follows that

[tex]F(3.2) = \boxed{0.7}[/tex]

(c) Expectation is defined as

[tex]E[X] = \displaystyle \sum_x x\,P(X=x)[/tex]

We have

[tex]E[X] = \displaystyle \sum_{x\in\{-1,0,2,6,7\}} x\,P(X=x) \\\\ E[X] = -P(X=-1) + 2P(X=2)+6P(X=6)+7P(X=7) \\\\ E[X] = -0.3 + 0.6 + 1.2 + 0.7 = \boxed{2.2}[/tex]

(d) First compute the second moment of X, which is defined as

[tex]E[X^2] = \displaystyle \sum_x x^2\,P(X=x)[/tex]

We get

[tex]E[X^2] = (-1)^2P(X=-1) + 2^2P(X=2) + 6^2P(X=6) + 7^2P(X=7) \\\\ E[X^2] = 0.3 + 1.2 + 7.2 + 4.9 = 13.6[/tex]

Variance is defined as

[tex]\mathrm{Var}[X] = E[(X - E[X])^2] = E[X^2] - E[X]^2[/tex]

so it follows that

[tex]\mathrm{Var}[X] = 13.6 - 2.2^2 = \boxed{8.76}[/tex]

(e) Not sure what this part has to do with the rest of the question. At any rate, if Y is a random variable following a Poisson distribution with λ = 3, then Y has a PDF of

[tex]P(Y=y) = \begin{cases}\dfrac{e^{-3}\times3^y}{y!}&\text{if }y\in\{0,1,2,\ldots\}\\\\0&\text{otherwise}\end{cases}[/tex]

Then

[tex]P(Y > 5) = 1 - P(Y \le 5) = 1 - P(Y=0) - P(Y=1) - \cdots - P(Y=5) \\\\ P(Y>5) = \dfrac{5e^3-92}{5e^3} \approx \boxed{0.0839}[/tex]


Related Questions

Cuál es el valor de la siguiente expresión?

(6 + 27) / (5 - 2)

Answers

Answer: 11

Step-by-step explanation:

6+27=33

33/3 = 11

John's bank account was overdrawn. The status of his account was -$133. He did not realize the problem and wrote another check for $55. The bank charged him a $22 fee for being overdrawn.

What was the new status of John's account at this point?

Answers

Answer:

210

Step-by-step explanation:-133-55-22=210

Find the constant C such that x ^ 3 - 3x + 5 <= C where x in[0,3] 18 23 14 17 21

Answers

Plug in maximum value of x (3) and see what you get. The maximum value of the expression when plugged in is C.

[tex]3^3-3\cdot3+5=C[/tex]

[tex]27-9+5=C\implies 23=C[/tex]

Now that means,

[tex]x^3-3x+5\leq 23[/tex] for any x in [tex][0,3][/tex]

Hope this helps :)

5*213 is a 5 digit number replace the * number by smallest digit to make them divisible by 3​

Answers

Answer:

1

Step-by-step explanation:

that is the answer

because 51213÷3=17071

4
...................

Things did not go quite as planned. You invested ​$21360​, part of it in a stock that paid​ 12% annual interest.​ However, the rest of the money suffered a​ 5% loss. If the total annual income from both investments was ​$​, how much was invested at each​ rate? How much money was invested at​ 12% annual​ interest?

Answers

Answer:

1992

Step-by-step explanation:

Let x be the amount invested at 12%.

Then the rest amount is (21360-x) dollars.

The 12% stock earning is 0.12x dollars.

The rest amount loss  is 0.05*(21360-x) dollars.

Your equation is

interest - loss            = total interest,    or

0.12x     - 0.05*(21360-x) = 1992    dollars.

Simplify and solve for x.

Please Help!!! Will give brainliest

Answers

Answer:

except of (g) all limits exist

Step-by-step explanation:

All the solutions are in the picture.

what is the population of nepal​

Answers

28.61 million (2019)

29,136,808 people (2020)
Nepal 2020 population is estimated at 29,136,808 people at mid year according to UN data. Nepal population is equivalent to 0.37% of the total world population. Nepal ranks number 49 in the list of countries (and dependencies) by population.
28.61 million (as of 2019)

16. Simplify: look at picture
please give detailed steps!!

Answers

Answer:

[tex] 2\sqrt{3} [/tex]

Step-by-step explanation:

1. Expand the expression

[tex] \frac{6}{ \sqrt{3} } \times \frac{ \sqrt{3} }{ \sqrt{3} } [/tex]

2. To multiply the fractions, multiply the numerators and denominators seperately

[tex] = \frac{6 \sqrt{3} }{ \sqrt{3} \sqrt{3} } [/tex]

3. Calculate the product : when a square root of an expression is multiplied by itself, the result is that expression.

[tex] \frac{6 \sqrt{3} }{3} [/tex]

4. Reduce the fraction with 3 and the solution is :

[tex] = 2 \sqrt{ 3} [/tex]

Martina took a train to the bullfight. It traveled 544 km nonstop in 8.5 hours to get there. If the train moved at a steady speed, what was the rate of speed

Answers

Answer:

64 km per hour

Step-by-step explanation:

544/8.5=64

a Find the sum of interior angle of the heptagon

Answers

Answer:

sum of the interior angles=900°

Answer:

900°

Step-by-step explanation:

To find any shape sum of interior angles ,

we use the formula,

(n-2)180°, where n is the number of sides

So for heptagon,

n=7

using formula,

(7-2)180°

=> 5(180)

=> 900°

Each byte contains 8 bits of information. Write an equation to represent the relationship between the number of packets of information and the number of bits. Be sure to define your variables.

Answers

Answer: 8b

Step-by-step explanation:

Equation:

Let b equal the number of bytes

byte = 8b

2 Why does it make sense to add 8 + 2 to make a ten and make new problem, 10 + 4?​

Answers

Step-by-step explanation:

Hahahaha this is math.lol

Find the number of steel ball bearings, each of diameter 0.7 cm, which can be made from 1 kg of steel, given that 1 cm' of steel has a mass of 7.85 g.​

Answers

Answer:

707.7, or 707

Step-by-step explanation:

0.18 x 7.85 g = 1.413 g/one bearing. Total amount of bearings: 1kg = 1000 g/1.413

need the answer as soon as possible

Answers

Answer:

soln

Step-by-step explanation:

=21÷x-2s

=21÷7-2×9

=3-18

=-15

Adult tickets for a movie cost six dollars and children's tickets cost three dollars if two adults and three children go to the movies how much will they pay?

Write a numerical or algebraic expression for each verbal phrase

Answers

They would pay $21 in total
2($6)+3($3)=$21

What is the volume of the right rectangular prism?

a) 21cm^3
b) 42cm^3
c) 120cm^3
d) 240cm^3

Answers

Answer:

c part is correct answer

Answer: D) 240 cm^3

Step-by-step explanation:

On edge

I want to know how to solve this.

Answers

Answer:

B

I just did it and got it right

Joshua spent 3/100 of the money he earned from mowing lawns on a gift for his mother.com what percent of his earning did Joshua spend?

Answers

He spent 3% of his money!

Answer:

3%

How did I get it?

3/100 as a decimal is 3% (3%/100)

How many different sets of answers are possible on a true-false test that has 11
questions?

Answers

2048 different sets are possible

Define bisector of a line​

Answers

Answer:

The line that divides something into two equal parts. You can bisect line segments, angles, and more.

Step-by-step explanation:

A bisector is what divides a line into two equal parts.

What’s x = in this equation

Answers

Answer:

5m

Step-by-step explanation:

Applying Pythagoras theorem:

a² + b² = c² (where a is base length, b is the height and c is the hypotenuse of the right triangle)

3² + 4² = c²

c² = 9 + 16 = 25

c = x = [tex]\sqrt{25}[/tex] = 5

∴ x = 5m

The perimeter of a rectangle is 332cm and the width is 76cm. Find the rectangle’s length

Answers

length = 90cm

solution: 332 - 76 - 76 = 180
180 ÷ 2 = 90

determine the area and perimeter​

Answers

Answer:

Area is the total surface covered by the shape and perimeter is the total length of the shape.

a continuous random variable is uniformly distributed in the interval a<X<b the Lower quartile is 5 and upper quartile is 9 find
a. the values of a and b
b. p(6<X<7)
c. the cumulative distributive function

راز​

Answers

(a) X has a probabiliity density of

[tex]f_X(x) = \begin{cases}\dfrac1{b-a}&\text{if }a<x<b\\0&\text{otherwise}\end{cases}[/tex]

If the lower quartile is 5 and the upper quartile is 9, then

[tex]\displaystyle \int_a^5 f_X(x)\,\mathrm dx = 0.25 \text{ and } \int_9^b f_X(x)\,\mathrm dx = 0.25[/tex]

Computing the integrals gives the following system of equations:

[tex]\displaystyle \int_a^5\frac{\mathrm dx}{b-a} = \frac{5-a}{b-a} = 0.25 \\\\ \int_9^b \frac{\mathrm dx}{b-a} = \frac{b-9}{b-a} = 0.25[/tex]

5 - a = 0.25 (b - a)   ==>   0.75a + 0.25b = 5   ==>   3a + b = 20

b - 9 = 0.25 (b - a)   ==>   0.25a + 0.75b = 9   ==>   a + 3b = 36

Eliminate a :

(3a + b) - 3 (a + 3b) = 20 - 3×36

-8b = -88

==>   b = 11   ==>   a = 3

and so P(X = x) = 1/(11 - 3) = 1/8 for all 3 < x < 11.

(b)

[tex]\displaystyle P(6<X<7) = \int_6^7f_X(x)\,\mathrm dx = \int_6^7\frac{\mathrm dx}8 = \boxed{\frac18}[/tex]

(c) The distribution function is then

[tex]\displaystyle F_X(x) = \int_{-\infty}^x f_X(t)\,\mathrm dt = \begin{cases}0&\text{if }x\le3 \\ \dfrac x8 &\text{if }3<x<11 \\ 1&\text{if }x\ge11\end{cases}[/tex]

How many kilograms of tin will be required to make 250 kg of an alloy, if the alloy must contain 81% copper, 14% tin and 5% lead?

Answers

Answer:

35

Step-by-step explanation:

all are obeying a constant ratio

copper 81tin 14⇒?lead 5total 100 ⇒250?=250*14/100=35
the answer is 35bb. good luck. by.

X:3/2+1/2x=2x
I need to solve for x

Answers

Answer: x = 1

Step-by-step explanation:

Given

3/2 + (1/2)x = 2x

Multiply 2 on both sides to cancel out the denominator

2 · [3/2 + (1/2)x] = 2 · 2x

3 + x = 4x

Subtract x on both sides

3 + x - x = 4x - x

3 = 3x

Divide 3 on both sides

3 / 3 = 3x / 3

[tex]\boxed {x=1}[/tex]

Hope this helps!! :)

Please let me know if you have any questions

Add -13 + 5. 8 -8 -18 18

Answers

Do you mean by add all the numbers?
If so this would be the answer:

80

Point H is located at (-3,-2) on the coordnate plane. Point H'. What ordered pair describes the location of H'?

Answers

Answer:

You bought a

Step-by-step explanation:

the perimeter of a rectangular field is 342 yards. if the width of the field is 77 yards, what is its length

Anyone know the answer to this?
Quick response

Answers

A) 94 yards

Since you know that in order to find the perimeter, you use the equation 2L+2W.

342=2L+2(77)
342=2L+154
188=2L
94=L

3 - 2 + 6 - 1 steps to please

Answers

Answer:

the answer is 6

hope this helps:)

Answer:

6

Step-by-step explanation:

3-2 = 1

6-1= 5

5+1= 6 this is the answer hope it is help for u

Other Questions
Shreya has a photo that is 16 cm tall and 20 cm wide. She wants to put a frame around the photo which would have the same width all around.Represent the area of the whole frame as a polynomial in terms of the width around the photo.A.[tex]x^{2} + 36x + 320[/tex]B.[tex]-4x^{2} - 72x + 320[/tex]C.[tex]4x^{2} + 72x + 320[/tex]D.[tex]-x^{2} - 36x - 320[/tex] PLEASE HELP!!!How do the Aleutian volcanoes differ from the Cascades volcanoes? A light bulb uses 40.0 W of power when connected to a 110 V (DC) outlet. If the same bulb is connected to a European 220 V outlet, how much power will the bulb use? Name the social issues that you have chosen and motivate why you have chosen it What impact did Sinclairs book have on the era of Progressive reform? Jos Clemente Orozco was one of Mexico's greatest muralists. Which of his murals became known as the Sistine Chapel of the Americas?A. PrometheusB. OmniscienceC. Man of Fire Please please help, brainstorm ideas on how social media effects on your brain. please help I don't care if it's wrong just try your best. the graph below shows the solution to which system of inequalities. y>-3 and y calculate mass of MnO2 if 1 mole of KMnO4 completely burnt. 2KMnO4 -> K2MnO4+MnO2+O2 Terrell Davids' charge account statement shows an unpaid balance of $110.00. Themonthly finance charge is 2 percent of the unpaid balance. What is the new accountbalance? Which expression has a value of 48?A . (168)(2+4)B . 16(82+4)C . 168(2+4)D . (168)2+4 All of the following are civic duties except?Question 1 options:Obey lawsregister for the draft (males)vote in national electionspay taxes #1 What is one major central idea of Nurse and Spy in the Union Army? Answer in one or two complete sentences. #2 Name two details from the text that support the central idea you identified in question #1. In the space provided, write a paragraph analyzing the effects of Puritanism on democracy. In what ways did Puritan beliefs impact American democracy? How does American democracy differ from early Puritan beliefs? Which expression has the same value as 2 + (-3)?23O 2 - (3)Submit Answer0-2+(-3)-3 - 2o 16. Where is the volcano that isconsidered the highest mountain inthe Western Hemisphere?a. Ecuadorb. Hawaiic. Colombiad. Argentina Write the equations using point slope form. Then put into slope intercept form. (3,-4), m=2 and (-5,1), m=4/3 (help pls), What numbers are a distance of 68 unit from 18 on a number line?Select the locations on the number line to plot the points. Find the largest integer that is below Square root 10 evaluate the expression when x=3