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?​

Answers

Answer 1

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) 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% live within five miles, hence [tex]p = 0.55[/tex].

Item a:

This probability is P(X = 0) when n = 3(none of the first three) 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:

[tex]S = \frac{\sqrt{0.45}}{0.55} = 1.22[/tex]

The standard deviation is of 1.22 students.

Item d:

This probability is P(X = 3) when n = 5, 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]

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:

[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


Related Questions

Which parent function is represented by the graph?

Answers

Answer: D. The quadratic parent function.

Step-by-step explanation:

Quadratic functions have a parabola shape like the graph shown in the image.

Find the slope of each line. PLS HELP TYSMMMM!

Answers

Answer:

Step-by-step explanation:

1. (-4, -2) (4, 0)

   (0 + 2)/(4 + 4)= 2/8= 1/4

2. (-1, 2) (1, -3) = (-3 - 2)/(1 + 1) = -5/2

3. (-2, 3) (0, 0) = (0 - 3)/(0 + 2) = -3/2

4. (1, 1) (3,2) = (2 - 1)/(3 - 1)= 1/2

If ACD and BAC are alternate interior angles and mACD=101°

Answers

Answer is A. 101°

Step-by-step explanation:

Solve using elimination.

–4x + 9y = –18
–x − y = –11

Answers

To do elimination, you need to get same coefficient before the variable
Multiply (-x-y = -11) by 4
-4x + 9y = -18
-4x - 4y = -44
Now subtract
13y = 26, y = 2
Plug in y = 2 for any of the two equation
-x - 2 = -11
-x = -9, x = 9

Solution: x = 9, y = 2

12
Fill in the blank: What's the length of the missing
side?
Ilype your answer

Answers

Answer:

13

Step-by-step explanation:

Using Pythagoras Theorem:

[tex]a^2+b^2=c^2[/tex]

Substitute values of a and b:

[tex]5^2+12^2=25+144=169[/tex]

[tex]c^2=169\\c=13[/tex]

The length of the missing side is 13.

7x+3y=m, solve for y

Answers

Y= (m-7x)/3

We need to subtract 7x on both sides
Then divide the entire thing by 3

A photo is 4 inches tall and 6 inches wide. To be proportional, how tall would the photo need to be if it were 10 inches wide?

Answers

Answer:

6[tex]\frac{2}{3}[/tex] inches tall

Step-by-step explanation:

4:6 = x:10

We can set it up like this:

[tex]\frac{4}{6}=\frac{x}{10}[/tex]

And then cross multiply & solve:

40 = 6x

6[tex]\frac{2}{3}[/tex] = x

Have a nice day!

     I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)

- Heather

b. 2x^2 + 15 _<13x solve polynomial inequality by factoring.​

Answers

Answer:

x<5   or  x<3/2

Step-by-step explanation:

2[tex]x^{2}[/tex]-13x+15<0

2[tex]x^{2}[/tex]-10x-3x+15<0

2x(x-5)-3(x-5)<0

(x-5)(2x-3)<0

x-5<0  or 2x-3<0

x<5  or  x<3/2

Which humanist idea was inspired by ancient Greeks and Romans?
O The government should protect the rights of citizens.
O People should have a say in how their churches are run.
O Formal education is the best way to improve people's lives.
O People can understand the world by using logic and reason to study it.

Answers

Answer:

the answer is c

Step-by-step explanation:

its the right answer lol

Answer:

(C) Formal Education is the best way to improve people's lives

Personally I thought it was (D) but now that I think about it...well yeah

Give an example of an equation whose solution is 5

Answers

Answer:

x - 5 = 0

Step-by-step explanation:

x - 5 = 0

Add 5 on both sides,

x - 5 + 5 = 0 + 5

x = 5

The equation whose solution is 5,

" x - 5 = 0 "

Answer:

x-5=0 right answer

kkkkkksssxcvbb

the capacity of a water tank is 1000 litres if 7/10 parts is emptied how many litres of water is left?​

Answers

Answer:

700 liter

Step-by-step explanation:

because 1000 * 7/10 is 700

A survey 3,000 who bought a new car showed that 900 had problems. What is the relative frequency of the people that had problems. show steps for me

Answers

Answer:

30%

Step-by-step explanation:

Presuming that "survey 3,000" is the total and "900" is the factor who had problems then dividing the total amount by the amount of problems like equal the relative frequency of people that had problems

Math:

Amount of people you had problems / Amount of people who bought the new car.

900 / 3000 = 0.3

Now you need to multiply by 100% (because % in this case is a unit/measurement)

0.3 * 100% = 30%

If f(x)=8-5x, what is f(4p+3)

Answers

Answer:

-20p - 7

Step-by-step explanation:

f(x)=8-5x

f(4p+3) = 8 - 5(4p + 3)

= 8 - 20p - 15

= -20p -7

Select the correct answer from each drop-down menu.
A machine cuts a strip of carpet into two pleces. The length of the smaller plece is 5 meters greater than 4 the length of the larger piece. If
the length of the smaller piece is 12 meters, the length of the bigger plece is meters and the total length of the carpet is
meters.

Answers

Length of larger piece be x

Smaller piece=4x+5

x=12m

[tex]\\ \sf\longmapsto 4x+5=4(12)+5=60+5=65m[/tex]

Total length=65+12=77m

The length of the bigger piece is 1.75 meters and the total length of the carpet is 13.75 meters.

Given that length of the smaller piece is 12 meters.

The length of the smaller piece is 5 meters greater than 4 times the length of the larger piece.

Let's represent the length of the larger piece as "x."

Length of the smaller piece = 4 times the length of the larger piece + 5

12 = 4x + 5

Subtracting 5 from both sides:

12 - 5 = 4x

7 = 4x

Dividing both sides by 4:

7/4 = x

1.75 = x

So, the length of the bigger piece is 1.75 meters.

To calculate the total length of the carpet, we add the length of the smaller piece and the length of the bigger piece:

Total length of the carpet = Length of the smaller piece + Length of the bigger piece

Total length of the carpet = 12 + 1.75

Total length of the carpet is approximately 13.75 meters.

Therefore, the length of the bigger piece is 1.75 meters and the total length of the carpet is 13.75 meters.

To learn more on Equation:

https://brainly.com/question/10413253

#SPJ7


Please help if you can!

Answers

Answer:

-3

Step-by-step explanation:

that’s where the line intercepts with the y axis

Answer:

-3,0 is y intercept good luck

Find the missing length of each triangle and round to the nearest tenth.

Answers

Answer: 5 inches

Step-by-step explanation: We must use the Pythagorean theorem to solve this. Since the hypotenuse is always opposite of the right angle, we know that the hypotenuse is 13 and we can substitute the values into this formula: a^2 + b^2 = c^2

12^2 + b^2 = 13^2

144 + b^2 = 169

169 - 144 = 25 (this is b^2)

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

Thus, the value of x is 5 inches.

Would appreciate brainliest <3

Lin's family has completed 70% of a trip. They have traveled 35 miles. How far is the trip?

Group of answer choices

24.5 miles

59.5 miles

200 miles

50 miles

Answers

Answer:

70x = 35

100

cross multiply

70x= 35 × 100

70x= 3500

divide both side by 70

70x = 3500

70 70

x= 50miles

Shirley is making a map of Main Street, which runs west to east through town. She used the number line shown, where each unit on the number line represents a block of main street and town hall was placed at zero.

After walking Main Street, she noted the following statements in her notebook. The flower boutique is five blocks west of the pet store. The pet store is four blocks east of the bank. The bank is eight blocks west of the hardware store. The hardware store is three blocks east of the bookstore. The bookstore is two blocks east of town hall.

Shirley also made a note to place an empty store in the opposite location of the bank on the number line.

Where should Shirley plot the empty store?

Answers

Answer:

3

Step-by-step explanation:

bookstore is two blocks east of town hall: 0+2=2

the hardware store is three blocks east of the bookstore: 2+3=5

the bank is eight blocks west of the hardware store: 5-8=-3

place an empty store in the opposite location of the bank: opposite of -3 is 3

HELP ASAP PLZ!!!!!!!!

Answers

Step-by-step explanation:

Triangle KLN has 3 equal angles so all sides of it must be equal ( equilateral triangle)

y+3=10

y=7

Triangle LNM has 2 equal angles as in an isosceles triangle so LN= ML

So sides opposite to equal angles must be equal too

x-6=y+3

x-6= 10

x= 16

What is the equation of a line that passes through the points (3, 6) and (8, 4)?

Answers

To solve this problem you find the slope of the equation and then use that to plug in a given point to find b:

y=-2/5x+7.2

Answer:

[tex]y=-\frac{2}{5} x+\frac{36}{5}[/tex]

Step-by-step explanation:

→ Find the gradient

[tex]\frac{4-6}{8-3}= \frac{-2}{5} =-\frac{2}{5}[/tex]

→ Write into y = mx + c format

[tex]y=-\frac{2}{5} x+c[/tex]

→ Substitute in ( 3 , 6 )

[tex]6 = -\frac{6}{5} +c[/tex]  ∴ [tex]c = 6+\frac{6}{5} =\frac{36}{5}[/tex]

→ Rewrite into y = mx + c format

[tex]y=-\frac{2}{5} x+\frac{36}{5}[/tex]

right ANSWERS only plz i need help on how to do it also not just the answer plz and thank u

Answers

Answer:

option c

Step-by-step explanation:

because 2x +1= 0

2x/2= -1

x= -1/2

(5x-7)^2-1=8 solve for x

Answers

Answer:

[tex]x = \frac{70 + \sqrt{900} }{50}\\[/tex] or [tex]x = 2[/tex]

Or:

[tex]x = \frac{70 - \sqrt{900} }{50}\\[/tex] or [tex]x = \frac{4}{5}[/tex]

Step-by-step explanation:

Step 1 - Simplify by expanding the brackets:

[tex](5x - 7)^2\\(5x - 7)(5x - 7)\\25x^2 - 35x - 35x + 49\\25x^2 - 70x + 49 - 1\\25x^2 - 70x + 48 = 8[/tex]

Step 2 - Subtract 8 from both sides so the equation equals 0:

[tex]25x^2 - 70x + 48 - 8 = 8 - 8\\25x^2 - 70x + 40 = 0[/tex]

Step 3 - Use the quadratic formula:

[tex]x = \frac{-b +- \sqrt{b^2 - 4ac} }{2a}\\a = 25\\b = -70\\c = 40[/tex]

Plug variables in:

[tex]\frac{-(-70) +- \sqrt{(-70)^2 - (4 * 25 * 40)} }{2 * 25}[/tex]

[tex]\frac{70 +- \sqrt{4900 - 4000} }{50}\\\\\frac{70 +- \sqrt{900} }{50}\\[/tex]

So x is either:

[tex]x = \frac{70 + \sqrt{900} }{50}\\[/tex]

[tex]x = 2[/tex]

Or:

[tex]x = \frac{70 - \sqrt{900} }{50}\\[/tex]

[tex]x = \frac{4}{5}[/tex]

Hope this helps!

Two students are throwing water balloons at a target. Accuracy is measured as how close the balloon is from the
center of the target. Tory's distances from the center of the target are approximately Normally distributed with a
mean of 123 mm and a standard deviation of 31 mm. Adam's distances from the center is approximately Normally
distributed with a mean of 108 mm and a standard deviation of 47 mm. If 5 attempts for Tory and 3 attempts for
Adam are randomly selected, what is the probability that the mean distance from the center of the target for Tory is
more than for Adam?
O 0.3113
O 0.4923
O 0.6887
O 0.7427

Answers

Answer:

0.6887

Step-by-step explanation:

Using normal distribution, the probability of that mean distance from the center of the target for Tory is more than for Adam is 0.6887.

What is normal distribution?

Normal distribution is "continuous probability distribution that its symmetrical around its mean with most values near the central peak".

According to the question,

Tory's distances from the center of the target are normally distributed with a mean of 123mm and a standard deviation 31mm. Number of attempts for Tory is 5.

Adam's  distances from the center of the target are with a mean of 108mm and a standard deviation 47mm. Number of attempts for Adam is 3.

In order to find the probability of that mean distance from the center of the target for Tory is more than for Adam.

Normal distribution z =   (x-μ)/σ       x ~ (μ,σ)

When x = 108

z = (123 - 108)/47  [Adam's  distances from the center of the target are normally distributed with a mean of 108mm and a standard deviation of Adam is 31mm.]

= 0.3191

P(x > 108) = P(z > - 0.3191)

                = 1 - 0.3191   [since the probability of the normal curve is 1 and to find the area under tory mean is greater than the Adam mean only if we subtract 1 from z value]

                = 0.6887

Hence, Using normal distribution, the probability of that mean distance from the center of the target for Tory is more than for Adam is 0.6887.

Learn more about Normal distribution here

https://brainly.com/question/11943392

#SPJ2

350 items have donated to the community food pantry and 35 of the items are jars of peanut butter. What percent of the donated items are jars of peanut butter?

Answers

Answer:

The answer is 25% donated peanut butter

Step-by-step explanation: Easy

what is it called when a constant and variable are combined (math)​

Answers

Answer:

a 'term'

Step-by-step explanation:

3r means the constant 3 multiplied by the variable 'r'

.In TIPS, the classroom of Grade 7A has a section of a field that measures 4 x 10 3 feet
by 5 x 105 feet. Another section Grade 7B is measuring 6 x 10 4 feet by 3 x 104 feet
(a)What is the area of the Grade 7A?
(b)What is the area of the Grade 7B?
(c)Which section has larger area? And how much is larger?

Answers

Answer:It's easy for us to visualize a meter; that's about 3 feet. ... nm (10-9 m) to 100 nanometers (100 x 10-9 = 10-7 m) and the unique properties that arise.

Step-by-step explanation:

find the degree of the polynomial 5ab^3-7a^5c^2-5

Answers

Answer:

7

Step-by-step explanation:

as -7a^5c^2 term has two cofficient a and b and each have power.by adding power of one term we get 7

The circle below represents one whole . …. What percent is represented by the shaded area ?

Answers

Answer:

50%

Step-by-step explanation:

shaded area = 2/4

shaded area as a percentage ;

     2 / 4 x 100

  = 1 / 2 x 100

  = 1 / 1 x 50

  = 50%

Juan ate 26 carrots. Carmen ate 3 times as many carrots as Juan ate.
Select the multiplication equation that represents this situation.

Group of answer choices:

25 x 3 = 75

3 x 28 = 84

3 x 26 = 78

26 x 13 = 338

Answers

Answer:

It is the third one

Step-by-step explanation:

Answer:

3 x 26 = 78

Step-by-step explanation:

It's quite simple, when you look at the problem, it states Juan at 26 carrots. Carmen on the other hand ate 3 times as much. For the answer choices, they put Carmen's 3 first and Juan's 26 second.

Ivan was the 31st person in line. His position in line was just behind 5/9 of the total number of people in line. How many people were in line? HELP PLEASE WILL MARK BRAINLIEST

Answers

31=1-(5/9)x

30=-(5/9)x

x=54

The answer is 54 people.

hope this helps :)

Other Questions
ben baked 6 times as many cookies as francis. francis baked 42 cookies. how many cookies did ben bake Please help with this question. The word march would appear between the guide wordsmaple and matchmarsh and matchmatch and muzzleNO LINKS. help plz An electrician charges aservice fee of $89 plus anhourly rate of $35.Identify the y-interceptin this linear equation.HELPP. Puede ubicarse la Tierra en un mbito determinado? To get a free bonus gift, you must spend at least $100 in acertain department store on Tuesday. On Tuesday, Mary madepurchases of $15, $26.50, and $40. What is the least amount sheneeds to spend in order to be eligible for the bonus gift? Do you believe the media should be allowed to report on the actions of the U.S. military during times of war? Explain. Please help! I will give brainliest =D Please answer fast. I need help right now how many grams of lead (ii) iodide will be precipitated by adding sufficient Pb(NO3)2 to trace with 630mL of 0.268M Ki solution?2KI(aq)+Pb(NO3)2(aq) PbI2+2KNO3(aq) A mam le compr un reloj para el __________________.FiestaDa del PadreDa de la MadreDa de la Independencia What can you infer from the fact that nitrogen gas is useless to animals? Where would a first responder try to find a pulse inaa patient who has been knocked unconscious? ANSWER ASAPFor each table, write the equation that represents the price per ticket. Jess had 212 deer stickers. Jess gave 47 stickers to Sandy and 24 stickers to Mike. How many stickers does Jess still have? Help me out and answer correctly and if it's correct I will give brainliest 9.What area of the brain experiences rapid growth of synapses and subsequent elimination of those synapses that are not used often during adolescence I need help getting the answer to this -71+blank=21 a ball is thrown with a speed of 100 m/s at a height of 150 m take g equals 9.8 m per second calculate the time of flight,angle of projection,range pls help I don't know how to solve it What is the prime factorization of 270? solve pls brainliest