Which is the expected value of the random variable with given probability distribution ?
Answers
Answer:
Step-by-step explanation:
Let X be the RV we are talking about.
Expected value has different aliases, such as weighted average, mean, expectation, first moment and so on.
Okay, how do we calculate the average first, just sum all the values and divide by number of values. It comes from the basic assumption, which is choosing one of them is equally likely. What I mean by that is quite simple, above process what I talked about is just sum of the numbers times their probabilities. e.g. (a+b+c+d)/4 = a/4 + b/4 + c/4 + d/4. In the example, we assumed that probability of choosing any a, b, c and d is equally likely.
Then, why I use the term weighted average is the generalized situation of average, which is some of the numbers are repetitive. For instance, X can take the values a, b, c and d; however, X can take the value a 3 times more than d, X can take the value b 2 times more than d and c and d occurs with the same frequency at X, Therefore, if we take a sample, it is likely to be a, b, a, c, d, a, b or the permutation of this sample. Therefore the weighted average is 3 * a / 7 + 2 * b / 7 + c / 7 + d /7 or using normal average theorem (a + a + a + b + b + c +d) / 7. First, both of them are equal. Find the distribution and multiply the values with the probabilities of the distribution and sum them up or just add them and divide by number of sample. Second, if you check that, a has more weight, which means a can determine the direction of the average more. That is the logic behind the expected value.
Now, if X is a discrete RV (like in the above example), we know what we are going to do. What if X is a continuous RV ? X could take infinite values therefore if you divide a number with an infinite value, the probability of an individual value X could take is going to be 0. Therefore, we cannot calculate the expected value of chosen values individually; however, we can calculate the expected value of an interval by approximating with Riemann Sum or with a better choice, using integrals. Because, technically using Riemann Sum and quantizing the values and approximating the area of the curve is the same as we did above.
In conclusion, basically if X is a discrete RV and the values X could take is countably infinite,
If X is a discrete RV and the values X could take is finite,
if X is a continuous RV,
Related Questions
help me find the cube of 1000
Answers
Answer:
10 X 10 X 10
Step-by-step explanation:
if thts what you talking aboyt
6(x + 3) - (x + 4) = -11
Answers
Answer: x=-5
Step-by-step explanation:
Distribute
6(x+3)-1(x+4)=-11
6x+ 18-1(x+4)=-11
6x +18-x-4=-11
Subtract the numbers
6x +18-x-4=-11
6x +14-x=-11
Combine like terms
6x +14-x=-11
5x +14=-11
subtract 14 from both sides of the equation
5x +14=-11
5x +=14-14 = -11 -14
simplify
5x=-25
divide both sides
x=-5
A big league pitching coach tries to limit his pitchers to 110 pitches per game. If the pitcher has
already thrown 52 pitches, write and solve an inequality to find how many more pitches he can
throw before reaching the limit.*
Type your inequality AND your answer as a sentence.
Answers
The pitcher can throw 58 until he reaches the limit, hopefully I helped :)
select the equation that is equivalent to (x+5)2
Answers
Answer:
2x + 10
Step-by-step explanation: 2 * (x + 5) = 2x + 10
Determine the value of A
Answers
mutiple choice pls help ! ( link = report )
Answers
Answer:
24 units2
Step-by-step explanation:
Hope it helps !! :)
IF YOU COULD HELP OUT THAT WOULD BE GREAT :)
Answers
how do I solve this?? number 8
Answers
Answer:
135
Step-by-step explanation:
that line equals 180 degrees so just subtract 45 to get the value of x
Simplify each expression
Answers
Answer:
Simpify each expression :
1) B
2)B
3)C
4)A
5)A
6)C
Find each product, and simplify the expression :
7)B
8)A
9)A
Step-by-step explanation:
I will send the explanation in a little time.
Solve the equation. 25% of 80 =
Answers
Answer: 20
Step-by-step explanation:
.25(80)=20
Answer:
the answer is gonna be 20
Does anyone know this
Answers
Answer:
x=105 _ 72
33 degrees....
Calculate the value of the unknown angle
Answers
Answer:
80+2x=180°{co-interior angle}
2x=180-80
2x=100
x=50°
hope it helps.
Angle D = 80
Angle A+B+C+D = 360
Angle C = Angle A
Angle A = 2x
80+80+2x+2x = 360
160+4x=360
4x=360-160
4x=200
X=200/4
x=50
Probability mathematic
Answers
Answer:
1/9
Step-by-step explanation:
Probability = Expected outcome/Total outcome
From the given pi chart,
Total outcome = 360degrees (since the total angle in a circle is 360 degrees)
Since we to find the probability of scoring a 5, we can see that the angle when he scores a 5 is 40degrees, hence;
Expected outcome = 40degrees
Pr(scoring a 5) = 40/360
Pr(scoring a 5) = 1/9
Hence the probability of scoring a 5 is 1/9
Answer:
1/9
Step-by-step explanation:
Probability is the branch of mathematics concerning numerical descriptions of how likely an event is to occur, or how likely it is that a proposition is true. The probability of an event is a number between 0 and 1, where, roughly speaking, 0 indicates impossibility of the event and 1 indicates certainty.
Divide the number of events by the number of possible outcomes.
Ayo can y’all pls come up with a 4th grade math problem and then answer it
Answers
Answer:
-8 x -3 = 24.
Step-by-step explanation:
When to negatives are multiplied, they automatically become positive. Therefore, 8 x 3 = 24.
Answer:
(8x7)\2 + x =5
Step-by-step explanation:
8x7= 56 \2 28+x= 33
mack used this model to find the quotient of 588 ÷ 14
what equation shows the final step in finding the quotient?
Answers
Answer:B
Step-by-step explanation:
Answer:b
Step-by-step explanation:
Michael runs 3.5 miles in 30 minutes. If he continues at this rate for 2 hours, determine his rate of change.
Answers
Answer:
The answer would be 7mph.
Step-by-step explanation:
The rate of change is just miles per hour.
How to solve
y = x + 1
y = 5x + 13
Answers
Answer:
Substitute y=5x+13
[ 5x+13=x+1 ]
For y=5x+13
Substitute x=−3
y=5(−3)+13
5(−3)+13=−2
y=−2, x=−3
Step-by-step explanation:
Use the inequality 12>6(12x+2). Complete parts a and b.
Answers
Answer/ Step-by-step explanation:
12>6(12x+2)
Divide both sides by 6. Since 6 is positive, the inequality direction remains the same.
12/6 >12x+2
Divide 12 by 6 to get 2.
2>12x+2
Swap sides so that all variable terms are on the left hand side. This changes the sign direction.
12x+2<2
Subtract 2 from both sides.
12x<2−2
Subtract 2 from 2 to get 0.
12x<0
Product of two numbers is <0 if one is >0 and the other is <0. Since 12>0, x must be <0.
x<0
Hopefully i helped =3
Please help! if you do you will get 'Brainliest'
Answers
There is a bag with only red marbles and blue marbles.
The probability of randomly choosing a red marble is
4
9
.
There are 32 red marbles in the bag and each is equally likely to be chosen.
Work out how many marbles in total there must be.
Answers
Red marbles:total marbles
4 9
32 ?
(32*9)/4
288/4
=72 marbles
Three times a number, x, increased by four is equal to five times the number, x. Which equation can be used to solve
for x?
3x+5x4
3x+4-5x
3x +4+5x
3x-4-5x
Answers
Answer:
=5x⁴+3x
=-2x+4
=8x+4
=-2x-4
Step-by-step explanation:
hope it's help
What’s the answer to this?!!
Answers
Answer:
52
Step-by-step explanation:
Using the reverse Pythagorean Theorem we can get the answer quite easily. If A^2 + B^2 = C^2, then by that same logic, C^2 - A^2 = B^2. That means 62^2, or 3844, minus 39^2, or 1521, equals 2323. The square root of that is 52.
Hope that this helps!
PLEASE HELP! WILL GIVE BRAINEST!! FOR MY MATH EXAM. please answer the whole question. only a few sentences are needed thanks.
Jordan asked some of his classmates their favorite numbers from 1-20. The numbers he found are below.
6, 10, 4, 12, 20, 5, 3, 12, 10, 2, 18, 15
Find the:
a. Minimum
b. Q1
c. Median
d. Q3
e. Maximum
Answers
Answer:
a. Minimum: 2
b. Q1: 9/2 = 2 1/2
c. Median: 10
d. Q3: 27/2 = 13 1/2
e. Maximum: 20
The list shows the value of five accessories that Mary purchased for her cell phone. 29, 15, 22, 52, 38 What is the mean absolute deviation of the numbers in the list?
Answers
Answer:
11.04
Step-by-step explanation:
Given the data:
29, 15, 22, 52, 38
The mean absolute deviation :
Mean, m = Σx / n
n = sample size = 5
29 + 15 + 22 + 52 + 38 = 156
Mean = 156 / 5 = 31.2
Mean absolute deviation (MAD):
Σ|x - m| / n
(|29 - 31.2| + |15 - 31.2| + |22 - 31.2| + |52 - 31.2| + |38 - 31.2|) / 5
(2.2 + 16.2 + 9.2 + 20.8 + 6.8) / 5
55.2 / 5
= 11.04
how many apples would be left?
Answers
Hello!
Lets tackle each section separately!
So Robin gives the first group [tex]\frac{1}{8}[/tex] of the apples.
To find how many apples that is in standard form, we divide 40 by 8.
40 ÷ 8 = 5.
So the first group ate 5 apples.
The second group ate 4 apples.
We do not have to calculate anything since it is already in standard form.
The third group ate 20% of the apples.
To find 20% of forty we can multiply 40 by 0.20, since 0.20 is the decimal equivalent of 20%.
40 × 0.20 = 8.
The last group of children ate 8 apples.
Now we add each groups apple intake together.
5 + 4 + 8 = 17.
Finally, we subtract 17 from 40.
40 - 17 = 23.
There were 23 apples left.
waffletowne
The area of the base of a box is 825 square centimeters. It has a height of 26 centimeters. What is the volume of the box in cubic centimeters?
Answers
Answer: 4950 cubic centimeters.
Step-by-step explanation:
We know that, the volume of box = Base area x height
Given: area of the base of a box = 825 sq. centimeters
height = 6 centimeters.
Then, Volume of the box in cubic centimeters = 825 x 6
= 4950 cubic centimeters.
hence, the volume of the box in cubic centimeters = 4950 cubic centimeters.
Find the volume of the cylinder in terms of x and to the nearest tenth
Answers
Answer:
12.57 in^3
Step-by-step explanation:
The easiest way to do this is to find the area of the circle surface and multiply it by the height
to find area the formula is pi r^2 and we are given the radius
so we plug in pi(2^2)=pi(4)= roughly 12.57
then we multiply the area by the height which is 1 so it would be the same
12.57(1)=12.57
HELP PLEASE WILL CROWN BRAINLIEST!!
The temperature in Calgary at 9 a.m. was – 23 C.
By 11 a.m., it had warmed up by 8 C.
By noon, it had warmed up by another 3 C.
But by 2:00 p.m. it had cooled by 6 C.
What was the temperature in Calgary at 2:00 p.m.?
Answers
Answer:
-18 C°
Step-by-step explanation:
Warmed means add cooled means subtract
starting at -23 it warmed by 8 add 8
-15
it warmed by 3 more add 3
-12
then it cooled by 6 subtract 6
-18
In a right triangle, if a = 8 and c = 17, what is the correct setup to find the value of b?
Answers
Answer:
b = 15
Step-by-step explanation:
Assuming that the question is referring c as the hypothenuse, the Pythegorean theorem states: [tex]a^2+b^2=c^2[/tex].
Thus, [tex]b=\sqrt{c^2-a^2}=\sqrt{17^2-8^2}=15[/tex].
So b is 15.
Answer: b = 15
Step-by-step explanation:
Here, we need to know the formula for the relationship between the three sides of the right triangle: a² + b² = c².
a and b are legsc is hypotenuse--------------------------------------------------------------------
Given
a = 8
c = 17
Solve
a² + b² = c²
(8)² + b² = (17)²
64 + b² = 289
b² = 225
b = √225
b = 15Hope this helps!! :)
Please let me know if you have any questions
Plzz help mee!!! will mark brainiest
Answers
Answer:
Step-by-step explanation:
Functoin B, A, C
Explanation:...