solve the literal equation a + 4b = 5b - 3a for a
3. The value of x varies directly with y,
and when x = 21, y=3.
Find the value of x if y= 10.
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!
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
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
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.
685,327 round to the nearest thousand
Answer:
685,000
Step-by-step explanation:
Answer:
685327.000
Step-by-step explanation:
URGENT PLEASE
Heron's Formula:
In geometry, Heron's formula (sometimes called Hero's formula), named after Hero of Alexandria, gives the area of a triangle by requiring no arbitrary choice of side as base or vertex as origin, contrary to other formulas for the area of a triangle, such as half the base times the height. Use Heron's formula to find the area, in square centimeters, of ΔABC.
Question 6 options:
A)
16.541
B)
15.612
C)
14.704
D)
24.708
[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
HELP PLSSSS OMG Round answer to nearest tenth too I KEPT GETTING I WRONG
Answer: where is the picture?
What is the terminal point of the vector a = (2,4) based at P = (3, 4)?
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)
The books have been sorted into fiction and nonfiction. The number of fiction books is 5 less than 4 times the number of nonfiction books. The books are 70% fiction. Choose the equation that best represents this scenario.
x over quantity 4 times x minus 5 end quantity equals 30 over 100
x over quantity 4 times x minus 5 end quantity equals 30 over 70
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
what is 2.4g-2.4g-9.8g
Answer:
2.4g-2.4g-9.8g "-9.8 grams".
Step-by-step explanation:
You just have to subtract the masses.
Hope this helps :)
when is a number divisible by 6?
7<2m-23 what is the answer if someone knows
Answer:
the answer is m > 15.
hope this helps!
Flying against the wind, a jet travels 2190 miles in 3 hours. Flying with the wind, the same jet travels 9520 miles in 8 hours. What is the rate of the jet in still air and what is the rate of the wind?
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
Which equation represents the data in the table shown?
A) y = -2x
B) y = 2x + 3
C) y = -2x + 3
D) y = -2x - 3
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 :)
The length of pop music songs is normally distributed with meze length of 215 seconds and a szard
deviation of 38 seconds. What percent of pop songs have lengths between three and four minutes?
(1) 48%
(3) 61%
(2) 57%
(4) 67%
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
Evaluate the expression 16+1+2
i really need help with this quition
Answer:
I really need help with this question.*
Answer:
There is no question
Step-by-step explanation:
Hope you have a great day!!
help plz I have an f in the class
The table below shows the size of the graduating classes for to high schools.
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
What is the property of this math problem please help
Answer:
distributive property
Step-by-step explanation:
Because distributive property formula is a(b+c) = ab + ac
meaning that w(6+5) = 6w + 5w
This is a question I need help with
Answer:
55
Step-by-step explanation:
180=35+90+m∠3
There are m marbles in a bag. Write an expression for the number of marbles in the bag when 4 marbles are taken away
Answer:
m-4
Step-by-step explanation:
4 marbles taken away = -4 marbles
4(4 + 7x) + x 2 -6x +5
Which point on the number line could represent
-2
7?
ABC D
十十一十十一十
-5 -4 -3 -2 -1 0 1 2
+
4 5
3
A
O
B
ОО
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
If ΔPQR ≅ ΔTSR, what are the congruent corresponding parts?
Answer:
If ΔPQR ≅ ΔTSR
Angles:
P and T
Q and S
R and R
Lines:
PQ and TS
QR and SR
PR and TR
a box contains 3 white balls and 4 black balls. a ball is drawn at random the color is recorded and then the ball is put back in the box. find the probability of the event that at least one of the balls is white
Answer:
3/7
Step-by-step explanation:
In a group of 84 kids, three-sevenths bought their lunches.Of those who bought their lunches got a slice of pizza? Write your fraction in simplest form
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 fast please!!!
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
Suppose A and B are mutually exclusive events, and that P(B)=0.24 and P(A OR B)=0.27. Find P(A).
Step-by-step explanation:
(4 - x)(x - 4) = 16 - x2 help me please sir please help me please sir fasthelp me please sir please help mehelp me please sir please help mehelp me please sir please help mehelp me please sir please help me
Answer:
Step-by-step explanation:
this equals 0.03
In 2021, Miranda records net earnings from self-employment of $158,500. She has no other gross income. Determine the amount of Miranda's self-employment tax and her for AGI income tax deduction.
In your computations round all amounts to two decimal places. Round your final answer to whole number
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