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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:

In this problem:

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

Answer:

B

Step-by-step explanation:

since the value is -2 1/4, the point must be less than -2, so it cant be C or D. Since A is less than -3, it cant be A so the point is B

Answer:

55

Step-by-step explanation:

180=35+90+m∠3

Answer:

f(x)= 0.90(0.59x)

Step-by-step explanation:

The 10% discount will make it so the senior citizens will pay 90% of the price. 90%=0.90

Also we need to know that 0.59x means how much money per pound the bananas cost.

So when you put it together, you should get f(x)=0.90(0.59x)

58% of pop songs have lengths between three and four minutes

Z score is used to determine by how many standard deviations the raw score is above or below the mean. It is given by:

[tex]z=\frac{x-\mu}{\sigma} \\\\where\ x=raw\ score, \mu=mean,\sigma=standard \ deviation\\\\Given\ that:\\\\\mu=215,\sigma=38.\\\\For\ x=3\ min(180\ sec):\\\\z=\frac{180-215}{38}=-0.92\\\\For\ x=4\ min(240\ sec):\\\\z=\frac{240-215}{38}=0.71[/tex]

From the normal distribution table, P(180 < x < 240) = P(-0.92 < z < 0.71) = P(z < 0.71) - P(z < -0.92) = 0.7611 - 0.1788 = 0.5823 = 58%

Find out more at: https://brainly.com/question/15016913

Answer:

685,000

Step-by-step explanation:

Answer:

685327.000

Step-by-step explanation:

Answer: where is the picture?

Answer:

the answer is m > 15.

hope this helps!

The number of fiction books are 7 and number of non fiction books are 3 respectively

let

number of fiction books = x

number of non fiction books = y

x = 4y - 5

Total books = z

x = 70% of z

y = 30% of z

x + y = z

4y - 5 + 30%(z) = z

4y - 5 + 0.3z = z

4y - 5 = z - 0.3z

4y - 5 = 0.7x

4y - 5 = 0.7z

4(0.3z) - 5 = 0.7z

1.2z - 5 = 0.7z

-5 = 0.7z - 1.2z

-5 = - 0.5z

z = -5/-0.5

z = 10

Therefore,

the number of non fiction = 30% of z

= 0.3 × 10

= 3

number of fiction = 70% of z

= 0.7 × 10

= 7

Learn more about equation:

https://brainly.com/question/16450098

Answer:

I really need help with this question.*

Answer:

There is no question

Step-by-step explanation:

Hope you have a great day!!

Explanation:

Start at the point (3,4) which is the tail of the vector. We move 2 units to the right and 4 units up to arrive at (5,8) due to the vector a = <2,4>. Effectively, we're using the translation rule [tex](x,y) \to (x+2,y+4)[/tex]

In other words, we add 2 to the x coordinate and add 4 to the y coordinate of the point (3,4) to move to (5,8)

I think It's B. I'm not really sure thought.

Answer:

2017

Step-by-step explanation:

Adams high school                                     Butler High school

628, 625, 622, 619, 616, 613,                      436, 449, 462, 475, 488, 501

common difference = 625 - 628 = -3         common difference = 449-436 = 13

we can continue series like this              

613 - 3 = 610                            [2011]             501 + 13 = 514

610 - 3 = 607                           [2012]            514 + 13 = 527

607 - 3 = 604                          [2013]             527 + 13 = 540

604 - 3 = 601                           [2014]             540 + 13 = 553

601 - 3 = 598                           [2015]             553  + 13 = 566

598 - 3 = 595                          [2016]             566 + 13 = 579

595 - 3 = 592                          [2017]              579 + 13 = 592

I assume when they will become equal

so it is 2017

Answer:

what... how

Step-by-step explanation:

Answer:

70

Step-by-step explanation:

First you want to find the amount of x per 1 y so you divide 21 by 3 to get when x = 7 y = 1. Now you can just multiply 10 by 7 to get 70.

I hope this helps!

Answer:

Velocity of jet in still air is 970 miles per hour and velocity of wind is 210 miles per hour.

Step-by-step explanation:

Jet's velocity against wind is

3040/4 = 760 miles per hour and flying with wind it is

8260/7 = 1180 miles per hour.

Let the velocity of jet in still air be x miles per hour and velocity of wind be y miles per hour.

As such its velocity against wind is x − y and with wind is x + y and therefore

x − y = 760 and x + y = 1180

Adding the two 2 x = 1940 and x = 970 and y = 1180 − 970 = 210

Hence velocity of jet in still air is 970 miles per hour and velocity of wind is

210 miles per hour.

Actual Answer:

https://socratic.org/questions/flying-against-the-wind-a-jet-travels-3040-miles-in-4-hours-flying-with-the-wind

Answer:

C

Step-by-step explanation:

the y-axis is getting smaller by 2 so its -2 and the x-axis is getting bigger by 1 so its -2 times 1 which is -2 but then 0=3 so the equation would be y = -2 + 3 :)

Answer:

m-4

Step-by-step explanation:

4 marbles taken away = -4 marbles

La expresion que podemos utilizar para encontrar el valor de los lados del cuadrado :

R = [tex]\sqrt{x^{2}+16x+64}[/tex]

Answer:

[tex]11[/tex]

Step-by-step explanation:

[tex]\sf{Use\: the\: distance\: formula\: to\: determine\: the\: distance\: between\: two\: points.[/tex]

[tex]\sf{Distance=\sqrt{(x_2 - x_1)^2 + (y_2-y_1)^2}[/tex]

[tex]\mathrm{Plug\:the\:points}[/tex]

[tex]\sqrt{\left(4-\left(-7\right)\right)^2+\left(5-5\right)^2}[/tex]

[tex](4+7)^2=11^2\\(5-5)^2=0[/tex]

[tex]\sqrt{11^2+0}[/tex]

[tex]11^2+0=11^2\\\sqrt{11^2}[/tex]

[tex]\mathrm{Apply\:radical\:rule:\:}\sqrt[n]{a^n}=a,\:\quad \mathrm{\:assuming\:}a\:\mathrm{is\ greater\ than \:or\ equal\: to \:0}[/tex]

[tex]=11[/tex]

Answer:

We don't have the tax rate so I'll just explain how to do it

Step-by-step explanation:

158,500 multiplied by ( a unit of one subtracted (-) from the percentage of tax rate in decimal form ) is the total of money Miranda made after tax

Answer:

distributive property

Step-by-step explanation:

Because distributive property formula is a(b+c) = ab + ac

meaning that w(6+5) = 6w + 5w

The correct answer is C. 58

Hope this helps!

Step-by-step explanation:

the answer is 58 this is the result I hope I've helped

[tex]\qquad \textit{Heron's area formula} \\\\ A=\sqrt{s(s-a)(s-b)(s-c)}\qquad \begin{cases} s=\frac{a+b+c}{2}\\[-0.5em] \hrulefill\\ a=7.2\\ b=6.7\\ c=4.5\\ s=\frac{7.2+6.7+4.5}{2}\\[0.5em] \qquad 9.2 \end{cases} \\\\\\ A\sqrt{9.2(9.2-7.2)(9.2-6.7)(9.2-4.5)}\implies A=\sqrt{9.2(2)(2.5)(4.7)} \\\\[-0.35em] ~\dotfill\\\\ ~\hfill A\approx 14.704~\hfill[/tex]

Answer:

The answer is C. 14.704

Step-by-step explanation: I just took the test

Answer:

There's not enough information to answer the question.

Step-by-step explanation:

The question says that out of 84 kids, 3/7 bought their lunches. Then it asks how many of the 3/7 got pizza without providing a number of those who bought a different food. And so, there's not enough information to solve this question.

Answer:

2.4g-2.4g-9.8g "-9.8 grams".

Step-by-step explanation:

You just have to subtract the masses.

Hope this helps :)

Answer:

If ΔPQR ≅ ΔTSR

Angles:

P and T

Q and S

R and R

Lines:

PQ and TS

QR and SR

PR and TR