Consider randomly selecting a student who is among the 12,000 registered for the current semester in a college. Let X be the number of courses the selected student is taking, and suppose that X has the following probability distribution: x 1 2 3 4 5 6 7 f(x) 0.01 0.02 0.12 0.25 0.42 0.16 0.02 a. Find the cdf of X. b. Find the expected number of courses a student is taking this semester. c. Find the variance of X. d. Find the third quartile of this distribution.
Answer:
a)
[tex]P(X \leq 1) = 0.01[/tex]
[tex]P(X \leq 2) = 0.03[/tex]
[tex]P(X \leq 3) = 0.15[/tex]
[tex]P(X \leq 4) = 0.40[/tex]
[tex]P(X \leq 5) = 0.82[/tex]
[tex]P(X \leq 6) = 0.98[/tex]
[tex]P(X \leq 7) = 1[/tex]
b)
4.61
c) 1.1579
d) 5 is the third quartile of this distribution.
Step-by-step explanation:
We are given the following discrete distribution:
[tex]P(X = 1) = 0.01[/tex]
[tex]P(X = 2) = 0.02[/tex]
[tex]P(X = 3) = 0.12[/tex]
[tex]P(X = 4) = 0.25[/tex]
[tex]P(X = 5) = 0.42[/tex]
[tex]P(X = 6) = 0.16[/tex]
[tex]P(X = 7) = 0.02[/tex]
a. Find the cdf of X.
Probability of X being less of equal to x. Than
[tex]P(X \leq 1) = P(X = 1) = 0.01[/tex]
[tex]P(X \leq 2) = P(X = 1) + P(X = 2) = 0.01 + 0.02 = 0.03[/tex]
[tex]P(X \leq 3) = P(X \leq 2) + P(X = 3) = 0.03 + 0.12 = 0.15[/tex]
[tex]P(X \leq 4) = P(X \leq 3) + P(X = 4) = 0.15 + 0.25 = 0.40[/tex]
[tex]P(X \leq 5) = P(X \leq 4) + P(X = 5) = 0.4 + 0.42 = 0.82[/tex]
[tex]P(X \leq 6) = P(X \leq 5) + P(X = 6) = 0.82 + 0.16 = 0.98[/tex]
[tex]P(X \leq 7) = P(X \leq 6) + P(X = 7) = 0.98 + 0.02 = 1[/tex]
b. Find the expected number of courses a student is taking this semester.
Multiplication of every outcome by its probability.
[tex]E = 0.01*1 + 0.02*2 + 0.12*3 + 0.25*4 + 0.42*5 + 0.16*6 + 0.02*7 = 4.61[/tex]
c. Find the variance of X.
Multiplication of the squared subtraction of each value and the mean, multiplied by its probability. So
[tex]V = 0.01*(1-4.61)^2 + 0.02*(2-4.61)^2 + 0.12*(3-4.61)^2 + 0.25*(4-4.61)^2 + 0.42*(5-4.61)^2 + 0.16*(6-4.61)^2 + 0.02*(7-4.61)^2 = 1.1579[/tex]
d. Find the third quartile of this distribution.
100*(3/4) = 75th percentile
The cdf passes 0.75 when X = 5, so 5 is the third quartile of this distribution.
Sorry this was the questions
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Answer:
(c) 90 m
Step-by-step explanation:
The perimeter is the sum of the side lengths. Each of the lower-right and lower-left indents can be reversed to make the figure a 20 m by 25 m rectangle without changing the perimeter. Then the perimeter is ...
P = 2(L +W)
P = 2(25 m + 20 m) = 2(45 m)
P = 90 m
_____
If you start at the upper left corner and work clockwise, the perimeter is the sum of segment lengths ...
P = 20 m + 5 m + 8 m + 20 m + 4 m + 20 m + 8 m + 5 m
P = 90 m
__
The units must be given as part of the measurement of the perimeter. That is why choice B (90) is inappropriate.
anybody!? I need help
Answer: D
Step-by-step explanation:
the profits from eds plumbing company increased by 14,460, or 30% this year. what profit did the company esrn last year?
The profit of plumbing company from eds earn last year, 48200
What is the percentage?The percentage is a mathematical term, which means a number or a ratio which is represented in fractions of 100. We use the '%' symbol to represent the percentage.
Formula for percentage;
Percentage = (present quantity/whole quantity)×100
Given that,
The profits from eds plumbing company increased by 14,460, or 30% this year
The profit company earned last year = ?
Suppose, last years profit = X
New profit = X + 0.30X = X + 14460
0.30X = 14460
X = 48200
Hence, the last years profit is 48200
To know more about Percentage check:
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The lengths of the sides of a triangle are in the extended ratio 4 : 5 : 8. The perimeter of the triangle is 85 centimeters. Find the length of the shortest side.
Answer:
the answer is 20
Step-by-step explanation:
The scale of floor plan is 1:250. Find the measurements in metres if 40 mm is drown on the plan
Given:
The scale is 1:250.
To find:
The measurements in metres if 40 mm is drown on the plan.
Solution:
The scale is 1:250. It means,
1 mm of the drawing = 250 mm of original length
40 mm of the drawing = 40×250 mm of original length
40 mm of the drawing = 10000 mm of original length
We know that,
1000 mm = 1 m
1 mm = 0.001 m
10000 mm = 10000×0.001 m
10000 mm = 10 m
Therefore, the measurement is 10 metres if 40 mm is drown on the plan.
What is the value of x?
60°
/700
x
0 130
O 110
60
050
Write an equation that is equivalent to 1/4 plus 1 plus 3/4 minus 2/3 minus 1/2
Answer:1/4 + 1/4 = 1/2 = 0.5
What is the number?
Help me
The total cost of 4 starfish was $7.20. Write and solve an equation to find how much one starfish cost.
Answer:
$1.80
Step-by-step explanation:
4x = 7.20
x = 1.80
From a rope that is 11 feet long, two pieces of length 13/5 feet and 3.3 feet are cut off. What is the length of the remaining rope?
Answer:
13/5 of 11 feet should be 343 inches aka 28.58 feet
28.58 feet minus 3.3 feet should be 25.28 feet
I believe your answer would be 25.28 feet or 303.36 inches
Step-by-step explanation:
3/5x2/3 Help pls thank you
Answer:
[tex]\frac{2}{5}[/tex]
Step-by-step explanation:
[tex]\frac{3}{5} *\frac{2}{3}\\=\frac{3*2}{5*3}[/tex]
The 3 in the numerator and the 3 in the denominator cancel out
[tex]= \frac{2}{5}[/tex]
I hope this helps!
A sample of 100 cars driving on a freeway during a morning commute was drawn, and the number of occupants in each car was recorded. The results were as follows: NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part. Occupants 1 2 3 4 5 Number of Cars 64 19 12 3 2 Find the sample median number of occupants.
Answer:
The sample median number of occupants is 1.
Step-by-step explanation:
Median:
The measure that separates the lower half of the distribution from the upper half.
In this question:
Total of 100 cars.
64 have 1 occupant.
19 have 2 occupants
12 have 3 occupants
3 have 4 occupants
2 have 5 occupants.
Median:
In the cumulative distribution
100/2 = 50
While we count until 64, it has 1 occupant, so 50 is one occupant, which means that the sample median is 1.
The sample median number of occupants is 1.
What is the scale factor between 4 cm and 10 cm?
B:10 cm
A:4 cm
Answer: B
Step-by-step explanation:
To find a scale factor between two similar figures, find two corresponding sides and write the ratio of the two sides. If you begin with the smaller figure, your scale factor will be less than one. If you begin with the larger figure, your scale factor will be greater than one. The ratio of any two corresponding lengths in two similar. geometric figures. Corresponding Angles: Angles in matching locations of two shapes
pleasee helpp meeee with this problemmmm
Answer:
C
Step-by-step explanation:
Answer:
I'm going to say B
Step-by-step explanation:
I hope this helps! If right may I please have brainliest? :)
PLEASE ANSWER ASAP FOR BRAINLEST!!!!!!!!!!!!!!!!!!!!!!!
Answer:
[tex]105km[/tex]
Step-by-step explanation:
It is given that; ([tex]2.5cm : 15km[/tex]) is the proportion by which distances are scaled down on a map. One can use this to make a proportion and solve to find how many ([tex]km[/tex]) would represent ([tex]17.5cm[/tex]). ([tex]x[/tex]) will represent the unknown or the number of ([tex]km[/tex]) that one has to solve for.
[tex]2.5 : 15 = 17.5 : x[/tex]
Cross products,
[tex]262.5 = 2.5x[/tex]
Inverse operations,
[tex]262.5 = 2.5x\\/2.5\\\\105 = x[/tex]
The list below shows all of the possible outcomes for flipping four coins.
Answer:
Each one has two possibilites, so the total is 2*2*2*2 = 16
Step-by-step explanation:
TTTT
TTTH
TTHT
TTHH
THTT
THTH
THHT
THHH
HTTT
HTTH
HTHT
HTHH
HHTT
HHTH
HHHT
HHHH
If you eliminate the duplicates, ie, the coins are identical, you get 4
TTTT
TTTH
TTHH
THHH
HHHH
Question 1 (1 point)
If three shares of TSLA cost $2400, how much would 8 shares cost?
a
$6400
b
$1100
c
$5400
d
$3200
Question 2 (1 point)
If twenty shares of GME cost $800, how many shares could I buy with $120?
a
16
b
3
c
4
d
1600
Question 3 (1 point)
If 8 shares of BB cost $72, how many shares could I buy with $810?
a
90
b
738
c
72
d
730
Question 4 (1 point)
If fifteen pencils cost $5, how much would 9 pencils cost?
a
$45
b
$3
c
$2
d
$14
Question 5 (1 point)
If four shares of AAPL cost $480, how many shares could I buy with $3600?
a
30
b
40
c
36
d
48
Can someone help be with those this is worth 100 points
Answer:
A
Step-by-step explanation:
2400/3= 800 800x8= 6400
Jim’s family is choosing whether to go to a restaurant for lunch or for dinner. The cost of a salad is $7 at lunch and $9 at dinner. The cost of a steak is $10 at lunch and $12 at dinner. Each person will choose either a salad or a steak regardless of the mealtime. Jim calculates the food bill to be $41 if they go during lunch and $51 if they go during dinner.
1.Write a system of equations that could be used to solve the problem. Define your variables.
2.Solve by any algebraic method (elimination/substitution). Work must be shown! How many people will choose a salad?
Answer:
3
Step-by-step explanation:
edge
Answer:
C. 3
Explanation:
edge 2020
pls pls pls pls helpppp
Answer:
$5.95
Step-by-step explanation:
7/20 = .35 cents per ounce
.35*17=5.95
Out of numbers: 5, 7, 21, 25, 28, 35, 42, 56, 75, and 80, choose those which are not factors of 42
Answer:
5, 25, 28, 35, 56, 75 80 are not the factors of 42
What’s the value of u , help please
Step-by-step explanation:
u-42+u-43+u-44=180
3u -129 = 180
3u = 309
u = 103
can u help solve this
Answer and Step-by-step explanation:
The expression is equal to 90.
This is because the lines that cut the right angle are cutting it in half, so those base angles are 45, leaving the center angle to be 90 (90 + 45 + 45 = 180).
90 = 19x + 4.5
85.5 = 19x
x = 4.5
The value of x that makes the parallelogram a square is 4.5.
I hope this helps!
#teamtrees #PAW (Plant And Water)
help me lol ........................
Answer:
A could be a possible answer actually
PLEASE HELP THIS ASSIGNMENT IS OVER DUE
Answer:
30
Step-by-step explanation:
Estimate the sum or difference 6/10+7/12
Step-by-step explanation:
in decimal format I got 1.183
the three is repeating
If Mario drives at a rate of 70 miles per hour, how long will it take him to drive 700 miles?
Answer:
dam mario u trying get a speeding ticket
bu the answer is 10 if im not mistaken
Step-by-step explanation:
Enter the value of w so the expression -5 +0.6W is equivalent to w (2.5 – 0.3w)
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Answer:
w = -2 or 8 1/3
Step-by-step explanation:
Setting the two expressions equal makes a quadratic equation:
-5 +0.6w = w(2.5 -0.3w)
0.3w^2 -1.9w -5 = 0 . . . . . . subtract the right-side expression
3w^2 -19s -50 = 0 . . . . . . . multiply by 10 to give integer coefficients
(3w -25)(w +2) = 0 . . . . . . . factor
We can use the zero product rule to find the solutions. The product will be zero only if a factor is zero.
3w -25 = 0 ⇒ w = 25/3 = 8 1/3
w +2 = 0 ⇒ w = -2
The values of w that make the two expressions equivalent are -2 and 8 1/3.
can you please help me with this question?
Answer:
I have made it in above picture
hope it helps
Question 4
Which of the following describes an equilateral triangle? Mark ALL that apply.
All angles are the same degree measure.
All sides are the same length.
Each angle measures 60°.
No sides are equal in length.
Each angle is a different measure.
Question 5
Answer:
A, B, & C
Step-by-step explanation:
An equilateral triangle is one that has (A) all equivalent angle measures & (B) all the sides are the same length.
since a triangle is equal to 180º, & since there are 3 angles in a triangle: (C) each angle measures 60º.
Hope this helps! Have a great day!