2. Suppose that you are looking for a student at your college who lives within five miles of you. You know that 55% of the 25,000 students do live within five miles of you. You randomly contact students from the college until one says he or she lives within five miles of you.
(a) What is the probability that you need to contact four people?
(b) How many students from the college you expect to contact until you find one lives within five miles of you?
(C) What is the standard deviation of the number of students to be contacted until one says who lives within five miles of you?
(d) Suppose you randomly ask 5 students at your college, what is the probability that 3 of them live within five miles of you?
(e) Suppose you randomly ask 5 students at your college, what is the expected number of students who live within five miles of you?
How to do this five questions ? thanks
Using the binomial distribution, it is found that:
a) There is a 0.0501 = 5.01% probability that you need to contact four people.
b) You expect to contact 1.82 students until you find one who lives within five miles of you.
c) The standard deviation is of 1.22 students.
d) There is a 0.3369 = 33.69% probability that 3 of them live within five miles of you.
e) It is expected that 2.75 students live within five miles of you.
For each student, there are only two possible outcomes. Either they live within 5 miles of you, or they do not. The probability of a student living within 5 miles of you is independent of any other student, which means that the binomial distribution is used to solve this question.
Binomial probability distribution
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
The parameters are:
x is the number of successes.n is the number of trials.p is the probability of a success on a single trial.In this problem:
55% of the students live within five miles of you, thus [tex]p = 0.55[/tex].Item a:
This probability is P(X = 0) when n = 3(none of the first three living within five miles of you) multiplied by 0.55(the fourth does live within five miles), hence:
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{3,0}.(0.55)^{0}.(0.45)^{3} = 0.091125[/tex]
[tex]p = 0.091125(0.55) = 0.0501[/tex]
0.0501 = 5.01% probability that you need to contact four people.
Item b:
The expected number of trials in the binomial distribution until q successes is given by:
[tex]E = \frac{q}{p}[/tex]
In this problem, [tex]p = 0.55[/tex], and 1 trial, thus [tex]q = 1[/tex], hence:
[tex]E = \frac{1}{0.55} = 1.82[/tex]
You expect to contact 1.82 students until you find one who lives within five miles of you.
Item c:
The standard deviation of the number of trials until q successes are found is given by:
[tex]S = \frac{\sqrt{q(1 - p)}}{p}[/tex]
Hence, since [tex]q = 1, p = 0.55[/tex]:
[tex]S = \frac{\sqrt{0.45}}{0.55} = 1.22[/tex]
The standard deviation is of 1.22 students.
Item d:
This probability is [tex]P(X = 3)[/tex] when [tex]n = 5[/tex], hence:
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 3) = C_{5,3}.(0.55)^{3}.(0.45)^{2} = 0.3369[/tex]
There is a 0.3369 = 33.69% probability that 3 of them live within five miles of you.
Item e:
The expected value of the binomial distribution is:
[tex]E(X) = np[/tex]
Hence, since [tex]n = 5, p = 0.55[/tex]:
[tex]E(X) = 5(0.55) = 2,75[/tex]
It is expected that 2.75 students live within five miles of you.
A similar problem is given at https://brainly.com/question/25343741
Please help please help please help please help
Answer:
2 , 3
Step-by-step explanation:
Hey everybody!
Can somebody please help me put with this problem?
I would really appreciate it if you could! Take a look!
Can someone please walk me through these 2 problems? I'm using the formula that the problem states but I have to be going wrong somewhere because all of my answers have been incorrect. The correct answers are below, but I have no idea how to get to them.
35: -13 - 34j volts
37: 28 + 57j volts
[tex]\boxed{35}~~ \begin{cases} I=2-7j\\ Z=4-3j \end{cases}\implies E=(2-7j)(4-3j) \\\\\\ \begin{array}{rllll} 4-3j\\ \times ~\hfill 2\\[-0.5em] \hrulefill\\ 8-6j \end{array}~~+ ~~ \begin{array}{rllll} 4-3j\\ \times ~\hfill -7j\\[-0.5em] \hrulefill\\ -28j+21j^2 \end{array}\qquad \implies 8-6j-28j+21j^2 \\\\[-0.35em] ~\dotfill\\\\ ~\hfill E=21j^2-34j+8~\hfill[/tex]
[tex]\boxed{36}~~ \begin{cases} I=3+10j\\ Z=6-j \end{cases}\implies E=(3+10j)(6-j) \\\\\\ \begin{array}{rllll} 6-j\\ \times ~\hfill 3\\[-0.5em] \hrulefill\\ 18-3j \end{array}~~+ ~~ \begin{array}{rllll} 6-j\\ \times ~\hfill 10j\\[-0.5em] \hrulefill\\ 60j-10j^2 \end{array}\qquad \implies 18-3j+60j-10j^2 \\\\[-0.35em] ~\dotfill\\\\ ~\hfill E=-10j^2+57j+18~\hfill[/tex]
What is the property used and the solution 4.(-3).5
Answer:
60
Step-by-step explanation:
using the bodmas
multiply 4 by -3
then multiply with 5
4. Ms. Bragg is giving a test worth 100 points. The test contains a total of 40 questions. Some questions are worth 2 points and some questions are worth 4 points on the test. Write a system of equations to determine how many of each type of question are on the test. A) Define your variables. You can use any letters you want) B) Write your system of equations. (There should be 2 separate equations)
9514 1404 393
Explanation:
A)
Let t and f represent the numbers of two-point and four-point questions, respectively.
__
B) The number of points for each type of question is the product of the point-value per question and the number of questions of that type.
2t + 4f = 100 . . . . . the test is worth 100 points
t + f = 40 . . . . . . . . there are 40 questions on the test
_____
Additional comment
The test will have 30 two-point questions and 10 four-point questions.
The pair of points (-4, y) and (5, 7) lie on a line with slope 1/3. What is the value of y? You must show all of your work to receive credit
Answer:
4
Step-by-step explanation:
[tex]slope = \frac{y - 7}{ - 4 - 5} = \frac{1}{3} [/tex]
y-7=-3, then y=4
Which equation represents a line passing through the point (8, 33) with a slope of 3?
A. y = 3x – 15
C. y = 3x – 8
B. y = 3x + 33
D. y = 3x + 9
Answer:
Is ka answers D ha.........
Answer:
The answer is D.
Step-by-step explanation:
(8 ,33) = ([tex]x_{1} , y_{1} )[/tex]
m = 3
To find the equation, use the formula:
y - [tex]y_{1}[/tex] = m(x - [tex]x_{1}[/tex])
Put the values in the equation
y - 33 = 3(x - 8)
y - 33 = 3x - 24
Now to get only the y, put the [tex]y_{1}[/tex]
y - 33 = 3x - 24
33 33
------------------------
y = 3x + 9
A club with 26 members is to select five officers (president, vice president, secretary, treasurer, and historian). In how many ways can this be done?
Answer:
9,687,600
Step-by-step explanation:
27P5
= 27!/(27-5)!
= 27!/22!
= 27*26*25*24*23
= 9,687,600
Today only, a sofa is being sold at a 32% discount. The sale price is $289.
What was the price yesterday?
Answer:
425$Step-by-step explanation:
Today only, a sofa is being sold at a 32% discount. The sale price is $289.
What was the price yesterday?
289 is 68% (100% - 32% = 68%)
289 : 68 * 100 =
425
--------------------------
check
425 - 32% = 289
the answer is good
The total age of a cat, dog, and a monkey is 4 years 2 months. The dog is twice as old as the cat. The monkey is twice as old as the dog. How old is the monkey? (Correct answer will get BRAINLIEST)
Answer:
50/7
Step-by-step explanation:
Solve
Let's solve your equation step-by-step.
4x+2x+x=50
Step 1: Simplify both sides of the equation.
4x+2x+x=50
(4x+2x+x)=50(Combine Like Terms)
7x=50
7x=50
Answer:
50/7
Step-by-step explanation:
Solve
Let's solve your equation step-by-step.
4x+2x+x=50
Step 1: Simplify both sides of the equation.
4x+2x+x=50
(4x+2x+x)=50(Combine Like Terms)
7x=50
7x=50
Functions
Domain and Range
1)
Check the 1st picture below.
the arrows at the end of the lines are stating that the lines are continuing indefinetely, or namely to infinity, the lines go to infinity upwardly as well as sideways.
3)
Check the 2nd picture below.
the graph has a hole when x = 6 for the domain, meaning it doesn't include that point, but includes any values before it down to -5 and including -5.
What is the median of these figure skating ratings? 5.0 6.0 7.0 7.5 8.0 9.0 10.0
The measure of an angle is 68.2°. What is the measure of its supplementary angle?
Answer:
x = 111.8°
Step-by-step explanation:
Supplementary angles are angles that add up to 180 degrees. Let x be the supplementary angle:
[tex]68.2+x=180\\x=111.8[/tex]
Solve 4x-4 < 7x - 19
Answer:
x<5
Step-by-step explanation:
cuz im a methnerd l
Answer:X>5
Step-by-step explanation:
What is the value for x if 2x+3=20 that makes the equation true
Answer:
x = 8.5
Step-by-step explanation:
2x+3=20
2x = 17...........subtract 3 from both sides
x = 8.5............divide both sides by 2
158) -.- A) P-3 in B) P-86 C) P-92 in D) P96 4
Answer:
P = 83 in
Step-by-step explanation:
For this one, all we need to do is substitute 7 for x and 4 for y:
3x + y = ?
3(7) + 4 =?
21 +4 = ?
21 + 4 = 25 in.
Now for the next one:
4y = ?
4(4) = ?
4(4) = 16
Now we solve the final side:
6x = ?
6(7) = ?
6(7) = 42
Now to find P, we must add them all together:
25 + 16 + 42 = 83
Therefore P = 83
Answer:
A) P = 83
Step-by-step explanation:
-=======================-
3x + y
3(7) + 4 =
21 + 4 =
25
-=======================-
6x
6(7)
42
-=======================-
4y
4(4)
16
-=======================-
25 + 16 + 42 = 83
Hope this helps.
For exercises 7-9 write expressions for the area of each rectangle in two different ways. Then find the area using each expressions.
Answer:
No Questions are shown here
Step-by-step explanation:
Just says "For exercises, 7-9 write expressions for the area of each rectangle in two different ways. Then find the area using each expression."
What is the slope and y intercept form of -5x + 3y =-9.
What is the slope and y intercept form of -x +2y =-20
fast help.
Answer:
y = 5/3x - 3 and y = 1/2x - 10
Step-by-step explanation:
A. -5x + 3y = -9
In order to go from standard to slope-intercept form, we want to isolate y on the left side. We start by adding 5x to both sides:
3y = -9 + 5x
Next, we divide both sides by 3:
y = (-9 + 5x)/3
And then distribute:
y = -9/3 + 5x/3
And finally simplify:
[tex]y = -3 + \frac{5}{3}x[/tex]
And move the numbers on the right to fit the form y = mx + b:
[tex]y = \frac{5}{3}x-3[/tex]
B. -x + 2y = -20
In order to go from standard to slope-intercept form, we want to isolate y on the left side. We start by adding x to both sides:
2y = -20 + x
Next, we divide both sides by 2:
y = (-20 + x)/2
And then distribute:
y = -20/2 + x/2
And finally simplify:
[tex]y = -10 + \frac{1}{2}x[/tex]
And move the numbers on the right to fit the form y = mx + b:
[tex]y = \frac{1}{2}x - 10[/tex]
4) A teacher has an annual income of $51,750. The income tax the teacher has to pay is 7%. What is the amount of income tax in dollar and cents the teacher has to pay?
A) $3,448.25
B) $3,622.50
C) $3,891.10
D) $3,933.01
9514 1404 393
Answer:
B) $3,622.50
Step-by-step explanation:
To find the tax, multiply the income by the tax rate:
$51,750 × 0.07 = $3,622.50
4 and 3x - 2 are both---------------- of 12x-8?
Thank you
Please if possible just include the answer not a link to the answer I can’t access them
Answer:
92%, because there is an 8% chance of landing on yellow.
50 points! Help (Vectors)
Answer:
[tex]<8,10>[/tex]
Step-by-step explanation:
Answer:
Blue (8,10)
Step-by-step explanation:
2(4)=8
2(5)=10
Solve for k:
k + 6 > -37
Answer:
[tex]\sf k + 6 > -37[/tex]
[tex]\sf k+6-6>-37-6[/tex]
[tex]\boxed{\sf k>-43}[/tex]
Answer:
Subtract 6 from both sides:
K +6 - 6 > - 37 - 6
Simplify the arithmetic:
k > - 37 - 6
Simplify the arithmetic
k > - 43
The figure below is a square with an area of 625 square centimeters. The length of a rectangle is 40% more than the length of the square. Find the length of the rectangle.
For a square:
A = s2, where s = side (the length and the width are the same)
625 = s2
±25 = s
length of rectangle = 1.4 · length of square
length of rectangle = 1.4(25)
length of rectangle = 35
Find the length of a diagonal of a 6 inch square.
Answer:
Step-by-step explanation:
If square is split into two from diagonal then it forms two right angled triangles which are congruent.
Therefore we can use Pythagoras theorem as we know side
d^2=6^2+6^2
d=√72
d=6√2
d=8.485 inches
Method 2:
Using formula
d=s√2
d=6√2
d=8.485 inches
You can find length of diagonal of any square if you know the length of side using formula.
d=s√2
Where s is length of side
Create (or find) mathematical examples of the following;
1. Equation
2. Expression
3. Slope-Intercept Form
4. Slope Formula
5. Scientific Notation
6. Point-Slope Form
Answer:
Equation
2+5=9
Other i don't know
Write an integer to represent each situation
1. walking to the track 6 feet ______
2. digging 10 holes a day _____
3. writing 5 papers ______
Find the absolute value
1. /-3/3 2. /+3/3 3. /-2/
4. /-6/ 5. /+9/ 6. /-15/
7. /=32/ 8. /+32/ 9. /-47/
10. /+78/
Answer:
1. 6 2. 10 3. 5
for others see below
Step-by-step explanation:
1. 6 feet
2. 10 holes
3. 5 papers
1./-3/3=3*3=9
2. /3/3=3*3=9
3./-2/=2
4./-6/=6
5./9/=9
6. /-15/=15
7. /-32/=32
8. /32/=32
9. /-47/=47
10. /78/=78
Determine the Domain and Range for promblems 1 and 2.
Answer:
Nvgjvfknh
Step-by-step explanation:
Solve the system of equations algebraically.
3x−6y=−15
−9x+12y=21
Answer:
(3x-9x)+12y-6y=21-15
-6x+6y=6.
I think that is the answer
Answer:
(3, 4)Step-by-step explanation:
Solve the system by elimination.
Divide the second equation by 3 and add to fist equation:
3x - 6y - 9x/3 + 12y/3 = -15 + 21/33x - 3x - 6y + 4y = -15 + 7-2y = - 8y = -8/-2y = 4Find the value of x:
3x - 6*4 = - 153x - 24 = - 153x = 24 - 153x = 9x = 3