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]
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?
Answer:
210
Step-by-step explanation:-133-55-22=210
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?
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.
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.
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
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
Answer:
64 km per hour
Step-by-step explanation:
544/8.5=64
16. Simplify: look at picture
please give detailed steps!!
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]
X:3/2+1/2x=2x
I need to solve for x
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
Find the constant C such that x ^ 3 - 3x + 5 <= C where x in[0,3] 18 23 14 17 21
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 :)
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
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
(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]
Cuál es el valor de la siguiente expresión?
(6 + 27) / (5 - 2)
Answer: 11
Step-by-step explanation:
6+27=33
33/3 = 11
Define bisector of a line
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.
need the answer as soon as possible
Answer:
soln
Step-by-step explanation:
=21÷x-2s
=21÷7-2×9
=3-18
=-15
2 Why does it make sense to add 8 + 2 to make a ten and make new problem, 10 + 4?
Step-by-step explanation:
Hahahaha this is math.lol
How many different sets of answers are possible on a true-false test that has 11
questions?
determine the area and perimeter
Answer:
Area is the total surface covered by the shape and perimeter is the total length of the shape.
I want to know how to solve this.
Answer:
B
I just did it and got it right
Please Help!!! Will give brainliest
Answer:
except of (g) all limits exist
Step-by-step explanation:
All the solutions are in the picture.
what is the population of nepal
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.
Answer: 8b
Step-by-step explanation:
Equation:
Let b equal the number of bytes
byte = 8b
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?
Answer:
3%
How did I get it?
3/100 as a decimal is 3% (3%/100)
The perimeter of a rectangle is 332cm and the width is 76cm. Find the rectangle’s length
3 - 2 + 6 - 1 steps to please
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
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
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?
Answer:
35
Step-by-step explanation:
all are obeying a constant ratio
copper 81tin 14⇒?lead 5total 100 ⇒250?=250*14/100=355*213 is a 5 digit number replace the * number by smallest digit to make them divisible by 3
Answer:
1
Step-by-step explanation:
that is the answer
because 51213÷3=17071
What is the volume of the right rectangular prism?
a) 21cm^3
b) 42cm^3
c) 120cm^3
d) 240cm^3
Answer:
c part is correct answer
Answer: D) 240 cm^3
Step-by-step explanation:
On edge
a Find the sum of interior angle of the heptagon
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°
Point H is located at (-3,-2) on the coordnate plane. Point H'. What ordered pair describes the location of H'?
Answer:
You bought a
Step-by-step explanation:
What’s x = in this equation
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
Add -13 + 5. 8 -8 -18 18