The chances that a student will get 7 marks out of 10 in first attempt of a certain Quiz while attempting Quiz on BlackBoard LMS is 40%. Suppose that 20 students are selected at random then find a probability that i)Exactly 12 students will get 7 marks out 10 in the Quiz. ii)Fewer than 10 students will get 7 marks out 10 in the Quiz. iii)At least 5 students will get 7 marks out 10 in the Quiz.

Answers

Answer 1

Answer:

i) [tex]P(X=12)=0.0355[/tex]

ii) [tex]P(X<10)=0.7553[/tex]

iii) [tex]P(X\geq 5)=0.9490[/tex]

Step-by-step explanation:

Let's start by defining the random variable ⇒

[tex]X:[/tex] '' Number of students that will get 7 marks out of 10 in first attempt of a certain Quiz while attempting Quiz on BlackBoard LMS ''

[tex]X[/tex] is a discrete random variable.

The probability of a randomly selected student getting 7 marks out of 10 is 0.4

(This is a data from the question).

Now, if we assume independence between the students while they are doing the Quiz and also we assume that this probability remains constant , we can modelate [tex]X[/tex] as a binomial random variable ⇒

[tex]X[/tex] ~ Bi (n,p)

Where ''n'' and ''p'' are the parameters of the variable.

''n'' is the number of students attempting the Quiz and ''p'' is the probability that a student will get 7 marks out of 10 which is 0.4 ⇒

[tex]X[/tex] ~ Bi (20, 0.4)  in the question.

The probability function for [tex]X[/tex] is

[tex]p_{X}(x)=P(X=x)=\left(\begin{array}{c}n&x\end{array}\right)p^{x}(1-p)^{n-x}[/tex]    (I)

Where [tex]\left(\begin{array}{c}n&x\end{array}\right)[/tex] is the combinatorial number define as

[tex]\left(\begin{array}{c}n&x\end{array}\right)=\frac{n!}{x!(n-x)!}[/tex]

Replacing the parameters in the equation (I) ⇒

[tex]P(X=x)=\left(\begin{array}{c}20&x\end{array}\right)(0.4)^{x}(0.6)^{20-x}[/tex]    (II)

For i) we need to find [tex]P(X=12)[/tex]

Then, we only need to replace by [tex]x=12[/tex] in equation (II) ⇒

[tex]P(X=12)=\left(\begin{array}{c}20&12\end{array}\right)(0.4)^{12}(0.6)^{8}=0.0355[/tex]

For ii) we need to calculate [tex]P(X<10)[/tex]

This probability is equal to ⇒ [tex]P(X<10)=P(X\leq 9)[/tex] and to calculate it we need to sum [tex]P(X=0)+P(X=1)+P(X=2)+P(X=3)+P(X=4)+P(X=5)[/tex]

[tex]+P(X=6)+P(X=7)+P(X=8)+P(X=9)[/tex]

We can do it summing each term or either using any program.

The result is [tex]P(X<10)=P(X\leq 9)=0.7553[/tex]

Finally for iii) we need to find  ⇒ [tex]P(X\geq 5)[/tex]

This probability is equal to ⇒ [tex]P(X\geq 5)=1-P(X\leq 4)[/tex] ⇒

[tex]1-P(X\leq 4)=1-[P(X=0)+P(X=1)+P(X=2)+P(X=3)+P(X=4)][/tex]

Again we can find each term by using the equation (II) or either using a program. The result is [tex]P(X\geq 5)=0.9490[/tex]


Related Questions

A cab company charges $3.10 flat rate in addition to $0.85 per mile. Rex has no more than $15 to spend on a ride. Write an inequality that represents Rex's situation. How many miles can Rex travel without exceeding his limit? Round off your answer to nearest tenth.

Answers

Answer:

Step-by-step explanation:

Let the total number of miles Rex can travel be x;

If a cab company charges $0.85 per mile, then x miles will cost $0.85x

If the flat rate rate charge is $3.10, the total price for x miles will be;

0.85x + 3.10

Since Rex has no more than $15 to spend on a ride, the inequality to represent the equation will be;

0.85x + 3.10 ≤ 15 (less than or equal to means that the total value cannot exceed $15)

Next is to solve for x

Given

0.85x + 3.10 ≤ 15

subtract 3.10 from both sides

0.85x + 3.10-3.10 ≤ 15-3.10

0.85x ≤ 15-3.10

0.85x ≤ 11.90

x ≤  11.90/0.85

x ≤ 14

This means that Rex can travel 14 miles without exceeding his limit

Answer:

[tex]3.10 + 0.85m \leq 15[/tex]

[tex]m \leq 14.0[/tex]

Step-by-step explanation:

Given

[tex]Flat\ Rate = \$3.10[/tex]

[tex]Addition = \$0.85[/tex] (per mile)

[tex]Maximum\ Amount = \$15[/tex]

Required

Determine the inequality that represents the scenario and solve

Let the number of miles be represented by m.

The company's charges can be calculated using:

[tex]Flat\ Rate + Additional\ Charges * m[/tex]

Substitute values

[tex]\$3.10 + \$0.85 * m[/tex]

Rex can't exceed $15 implies that the company's charges can't exceed Rex's budget.

This is expressed as:

[tex]\$3.10 + \$0.85 * m \leq \$15[/tex]

[tex]\$3.10 + \$0.85m \leq \$15[/tex]

[tex]3.10 + 0.85m \leq 15[/tex] ---- The inequality

Solving for m: Collect Like Terms

[tex]0.85m \leq 15 - 3.10[/tex]

[tex]0.85m \leq 11.9[/tex]

Divide through by 0.85

[tex]m \leq 11.9/0.85[/tex]

[tex]m \leq 14.0[/tex] ---- The solution

Solve the triangle, find m∠A and m∠C. Round angles to the nearest degree.
m∠A= __∘

m∠C= __∘

Answers

Answer:

[tex]m\angle A=63^\circ\\m\angle C=26^\circ[/tex]

Step-by-step explanation:

Trigonometric Ratios

The ratios of the sides of a right triangle are called trigonometric ratios. The longest side of the triangle is called the hypotenuse and the other two sides are called the legs.

Selecting any of the acute angles as a reference, it has an adjacent side and an opposite side. The trigonometric ratios are defined upon those sides.

The cosine ratio is defined as:

[tex]\displaystyle \cos\theta=\frac{\text{adjacent leg}}{\text{hypotenuse}}[/tex]

Note the angle A of the figure has 17 as the adjacent leg and 38 as the hypotenuse, so we can directly apply the formula:

[tex]\displaystyle \cos A=\frac{17}{38}[/tex]

[tex]\cos A=0.4474[/tex]

Using a scientific calculator, we get the inverse cosine:

[tex]A=\arccos(0.4474)[/tex]

[tex]A\approx 63^\circ[/tex]

Since A+B+C=180°, we can solve for C:

C = 180° - A - B

C = 180° - 63° - 90°

C = 26°

Thus:

[tex]m\angle A=63^\circ\\m\angle C=26^\circ[/tex]

In the given right triangle ABC, m∠A ≈ 26.44° and m∠C ≈ 63.56°.

To solve the right triangle ABC, we can use trigonometric ratios. In a right triangle, the three main trigonometric ratios are:

1. Sine (sin): [tex]\(\sin(\theta) = \frac{{\text{opposite side}}}{{\text{hypotenuse}}}\)[/tex]

2. Cosine (cos): [tex]\(\cos(\theta) = \frac{{\text{adjacent side}}}{{\text{hypotenuse}}}\)[/tex]

3. Tangent (tan): [tex]\(\tan(\theta) = \frac{{\text{opposite side}}}{{\text{adjacent side}}}\)[/tex]

Given:

AC = 38

AB = 17

To find the angles m∠A and m∠C, we can use the sine and cosine ratios, respectively.

1. For m∠A:

[tex]\(\sin(m\angle A) = \frac{{AB}}{{AC}} = \frac{{17}}{{38}}\)\\\\\(m\angle A= \sin^{-1}\left(\frac{{17}}{{38}}\right)\)[/tex]

2. For m∠C:

[tex]\(\cos(m\angle C) = \frac{{AB}}{{AC}} = \frac{{17}}{{38}}\)\\\\\(m\angle C = \cos^{-1}\left(\frac{{17}}{{38}}\right)\)[/tex]

Let's calculate the angles:

[tex]1. \(m\angle A \approx \sin^{-1}\left(\frac{{17}}{{38}}\right) \approx 26.44^\circ\)\\\\2. \(m\angle C \approx \cos^{-1}\left(\frac{{17}}{{38}}\right) \approx 63.56^\circ\)[/tex]

Therefore, m∠A ≈ 26.44° and m∠C ≈ 63.56° (rounded to the nearest degree).

To know more about right triangle, refer here:

https://brainly.com/question/31613708

#SPJ2

A newspaper is rolled into a cylindrical shape of approximate diameter 4cm It is wrapped for posting with a strip of paper which goes about 2 1/2 times round the newspaper Use the value 3 for π to find the approximate length of the wrapping paper. And 2. Calculate the total surface area of a solid cone of slant hight 10cm and base diameter 10 cm.Use the value 3.14 for π

Answers

Answer:

30 cm

[tex]863.5\ \text{cm}^2[/tex]

Step-by-step explanation:

d = Diameter of cylinder = 4 cm

n = Number of times the strip of paper is turned = [tex]2\dfrac{1}{2}=2.5[/tex]

Diameter of the cylinder will be approximately equal to the diameter of the paper wound. Length of one turn will be circumference of the paper

Circumference of the paper

[tex]c=\pi d\\\Rightarrow c=3\times 4\\\Rightarrow c=12\ \text{cm}[/tex]

Total length of the paper will be the number of turns multiplied by the length of one turn

[tex]l=nc\\\Rightarrow l=2.5\times 12\\\Rightarrow l=30\ \text{cm}[/tex]

Length of the strip of paper is 30 cm.

2.

l = Slant height = 10 cm

d = Base diameter = 10 cm

r = Radius of base = [tex]r=\dfrac{d}{2}=\dfrac{10}{2}=5\ \text{cm}[/tex]

Total surface area of cone is given by

[tex]S=\pi r^2+\pi rl\\\Rightarrow S=\pi r(r+rl)\\\Rightarrow S=3.14\times 5(5+5\times10)\\\Rightarrow S=863.5\ \text{cm}^2[/tex]

The total surface area of cone is [tex]863.5\ \text{cm}^2[/tex].

Henry left for the lake in the morning and it was 78°F.
When he arrived at the lake the temperature had increased
7° and by lunch it increased another 5°. What is the
temperature when Henry was eating lunch?

Answers

Answer:

The temputure is -64

Step-by-step explanation:

Given the following linear function sketch the graph of the function and find the domain and range. ƒ(x) = -5x + 4

Answers

Answer:

Domain: (-∞,∞)

Range:(-∞,∞)

Step-by-step explanation:

The sketch of the given function has been attached and the domain and range both will be (-∞,∞ ).

What is a linear function?

A straight line on the coordinate plane is represented by a linear function.

A function that fluctuates linearly with respect to the changing variable is referred to as being linear.

A linear function always has the same and constant slope.

The formula for a linear function is f(x) = ax + b, where a and b are real values.

Given the function,

ƒ(x) = -5x + 4

Range of the function ;

Since the value of the function is defined for all real x and the value will be unique so

Range =  (-∞,∞ ).

The domain of the function ;

Since it is defined for all real x so,

Domain =  (-∞,∞ )

For more about the linear function

brainly.com/question/21107621,

#SPJ2

Brad had 10 crickets in his pet lizard’s cage. After one day, Brad’s lizard has eaten 20% of the crickets he had put in the cage. By the end of the next day, the lizard had eaten 25% of the remaining crickets. how many crickets were left in the cage at the end of the second day?

Answers

7.5 crickets left (I think)

20%=2

25%(of 2)=0.5

2+.5=2.5

10-2.5=7.5

Hope this helps:)

Choose the correct answer choice.

Answers

Answer:

The T shirt choice

Step-by-step explanation:

Both values increase at the same rate therefore is proportional.

What is the Value of the angle AEX

Answers

Answer:

52

Step-by-step explanation:

I take it that x is somewhere near the end of the diagonal line, so you want to know the value of 3x + 1???

We know that (3x + 1) + (2x + 4) = 90 degrees. That's because AEF = 90 degrees.

So begin by removing the brackets.

3x + 1 + 2x + 4 = 90                 Combine the like terms.

5x + 5 =90                               Subtract 5 from both sides.

5x + 5 - 5 = 90 - 5                   Combine  

5x = 85                                    Divide by 5

x = 17

3x + 1  = 3*17 + 1 = 51 + 1 = 52

I need help please ​

Answers

(-5,1) is the correct answer or option c:)

Solving the system using equations ( 15 points)
3x+2y=17
2x+5y=8

Answers

Answer:

{x,y}={  11 /69   ,−  11 /10  }

Step-by-step explanation:

Hellllllllllllppppppppppp

Answers

Answer:

The answer is 5 1/2! So what you are looking for is 1/2.

Step-by-step explanation:

Answer:

11/2

Step-by-step explanation:

A bag contains 95 blue marbles, 7 red marbles, and 5 green marbles. One marble is randomly
chosen. Select all true statements about the marble chosen.
A It is certain that the marble was blue.
B. It is unlikely that the marble chosen was green.
C. It is unlikely that the marble chosen was orange.
D. It is likely that the marble chosen was blue.
E It is not possible that the marble chosen was green.
E It is neither likely nor unlikely that the marble chosen was red.

Answers

Answer:

B,D, and the last E

Step-by-step explanation:

B,d,f is that good for you

QUICK!!!!!

Analyze the conditional statement below and complete the instructions that follow.

If m is the midpoint of AB, then M divides AB into two congruent segments.

Identify the inverse of the converse of the conditional statement.

O If M is not the midpoint of AB, then M does not divide AB into two congruent segments.

If M is the midpoint of AB, then M divides AB into two congruent segments.

If M divides AB into two congruent segments, then M is the midpoint of AB.

Olf M does not divide AB into two congruent segments, then M is not the midpoint of AB.

Answers

Answer:

D. If M does not divide AB into two congruent segments, then M is not the midpoint of AB.

Step-by-step explanation:

A conditional statement is one that include 'if'. Thus it is also referred to as an 'if' statement.

Given a conditional statement:

If M is the midpoint of AB, then M divides AB into two congruent segments.

The converse of the given statement is done by interchanging the two parts of it. So that we have:

If M divides AB into two congruent segments, then M is the midpoint of AB.

Then, the inverse can be obtained by getting the negative of both parts of the converse. Therefore, the inverse is:

If M does not divide AB into two congruent segments, then M is not the midpoint of AB.

The correct option is D.

Find tan-1 1.4281 to the nearest degree.
a. 10°
b. 55°
C. 5°
d. 35°

Answers

Answer:

[tex]\:x=55^{\circ \:\:}[/tex]

Therefore, option 'b' is correct.

Step-by-step explanation:

Let x be the angle

tan x = 1.4281

determining the [tex]\tan ^{-1}\left(1.4281\:\right)[/tex]

[tex]\:\tan \:x\:=1.4281\:[/tex]

[tex]x=\tan ^{-1}\left(1.4281\:\right)[/tex]

[tex]\:x=55^{\circ \:\:}[/tex]

Therefore, option 'b' is correct.

44.8 is what percent of 160?

Answers

Answer:

28% .................

Answer:

28%

Step-by-step explanation:

100%/x%=160/44.8

(100/x)*x=(160/44.8)*x       - we multiply both sides of the equation by x

100=3.5714285714286*x       - we divide both sides of the equation by (3.5714285714286) to get x

100/3.5714285714286=x

28=x

x=28

now we have:

44.8 is 28% of 160

IL GIVE BRAINLIST!! PLEASE HELP! THERES 2 ANSWERS JUST SAYING!!​

Answers

Answer: Option 2

Pls mark me brainilest!

Step-by-step explanation:

I don’t understand.

Answers

Answer:

y = -2/3x

Step-by-step explanation:

A perpendicular line is the negative reverse of the slope of the other line. I'm not sure about the options you have there but hopefully this helps you get your answer.

A retail grocer bought a case of 12 packages of coffee for $52.32.

How much did the retailer pay for each package of coffee?


The retailer sold each package for $12.59.

What is the difference between the retailer’s cost and the selling price for each package of coffee?

Answers

Answer:

4.36

8.23

Step-by-step explanation:

Answer:

4.36

Step-by-step explanation:

3*10^4+2.5*10^0
ghfuigffhh

Answers

Answer:

30002.5

Step-by-step explanation:

An isosceles triangle has base angles that each measure 42 degrees.Which equation can be used to find z, the measure of the third angle of this isosceles triangle in degrees

Answers

Answer:

z+42+42=180

Step-by-step explanation:

Since it is an isosceles triangle, the two base angles are the same and remember all the angles add to  180. So use this equation:

z+42+42=180

If you need to find z, it is 96.

Check: 96+42+42=180

if g(x)=x²-2 and p(x)=2x+3, find (g·p)(x)

Answers

2X^3+3x^2-4x-6

You do x^2-2 times 2x+3 and use FOIL method to get answer

Same factory has supplies expenses of $1135.78 a day, in addition to the wages above and makes $60,128.72 in one week, what is the factory's total profit or loss in one week?

Answers

Given :

Factory has supplies expenses of $1135.78 a day.

Company earns $60,128.72 in one week.

To Find :

The factory's total profit or loss in one week.

Solution :

Expenses of factory of a week :

E =$( 1135.78 × 7 ) = $7950.46 .

Now, profit is given by :

P = $60,128.72 - $7950.46

P = $52178.26

Therefore, total profit of factory in one week is $52178.26 .

Hence, this is the required solution.

The figures below are similar. Find the length of the missing side.
90
10
7
Х
36
4
14
126
X=

Answers

Answer:

63

Step-by-step explanation:

multiply the side by 9

Justin and his children went into a grocery store and he bought $18 worth of bananas and mangos. Each banana costs $0.60 and each mango costs $1.50. He bought 2 more bananas than mangos. Graphically solve a system of equations to determine the number of bananas, x, and the number of mangos, y, that Justin bought.

Write an answer in y=mx+b form, please.
Two equations.

Answers

Answer:

x=10 and y= 8.

Step-by-step explanation:

Given that the cost of 1 banana = $0.60

Cost of 1 mango = $1.50.

Total cost= $ 18  

Here, x be the number of bananas and y be the numbers of mangos,

As the number of bananas is 2 more than the number of mangos,

So, x=y+2

[tex]\Rightarrow y=x-2 \cdots(i)[/tex]

Cost of x bananas [tex]=\$ 0.60 \times x[/tex]

Cost of y mangos [tex]=\$ 1.50 \times y[/tex]

Total cost = 0.6x+1.5y

[tex]\Rightarrow 18 = 0.6x+1.5y\\\\\Rightarrow 1.5y=18-0.6x\\\\\Rightarrow y= 12 - 0.4 x \cdots(ii).[/tex]

Solving both the equations (i) as well as (ii), graphically as shown in the figure by plotting both the graphs.

Both the graphs intersect at the point (10,8) as shown in the graph.

So, the solution of both the equations is, (x,y)=(10,8). i.e

The number of bananas = x= 10 and

the number of mangos = y = 8.

Can somebody plz answer all of them correct! (Only if u done this before)
thanks! WILL MARK BRAINLIEST
(Don’t judge me..I didn’t study so I need to do corrections)

Answers

Answer:

23) 53/100

24)2/5

25)3/5

26)11/50

27)17/50

28)19/1000

29)4/5

30)1/250

31)9/25

32)1 3/10

33)11 1/2

34) 7 3/40

Step-by-step explanation: Hope this helps!

What is the image point of (-3,3) after the transformation R180° 0 T-3, -4?

Answers

Answer:

Image point(6, 1)

Step-by-step explanation:

Given point → (-3, 3)

Transformation to be done → [tex]R_{180}0T_{-3,-4}[/tex]

Transformations to be done,

Step - (1). Translation of the given by 3 units left and 4 units down.

Step - (2). Followed by the rotation counterclockwise 180° about the origin.

Rule for step (1),

(x, y) → (x - 3, y - 4)

By this rule,

(-3, 3) → [(-3 - 3), (3 - 4)]

         → (-6, -1)

Rule for step -2,

(x, y) → (-x, -y)

(-6, -1) → (6, 1)

Therefore, following these two steps coordinates of the image point → (6, 1)  

One Saturday, a butcher sells a total of b pounds of beef at $6.00 per pound. She also sells some pork for $7.00. On Sunday she sells b pounds of beef again, but at the sale price of $4.00 per pound. She also sells some pork for $9.00. Given that she made the same revenue of d dollars each day, which of the following systems of equations can be used to find out how many pounds of beef, b, she sold each day?

Answers

The equations that can be used to find out how many pounds of beef, b, she sold each day will be:

d = 6b + 7.

d = 4b + 9

How to illustrate the equation?

From the information given, the butcher sells a total of b pounds of beef at $6.00 per pound and she also sells some pork for $7.00.

Therefore, the equation will be:

d = (6 × b) + 7.

d = 6b + 7.

d = (4 × b) + 9

d = 4b + 9

Learn more about equations on:

brainly.com/question/13448052

#SPJ1

what expression is equal to(5+x-2)×2

Answers

If you simply the equation it would be 6+2x

YALL BETTER ANSWER THIS PLSSSSSSSSSSS

Answers

Answer:

= 3/16(0.1875)

Step-by-step explanation:

explanation in the image.

Answer:

Step-by-step explanation:

Take out lignes

-1/4x-3/7

= -7/12

Can someone help me cuz i need help

Answers

Answer:

f

klllllllllk

Step-by-step explanation:

C and E are true
———————————
Other Questions
Archaeopteryx is an intermediate fossil that has characteristics of both dinosaurs and early birds. This is evidence for evolution because it shows *A. The change in species over timeB. Cross breeding between organismsC. The development of adaptationsD.The ability of a species to take on the characteristics of another What is one danger associated with the use of hydrogen gas Using the chart below, match the event to the era in which it occurred. Column A1.Dinosaurs roamed the Earth:Dinosaurs roamed the Earth2.Trilobites were one of the most dominant species:Trilobites were one of the most dominant species3.The era we currently live in:The era we currently live inColumn Ba.Mesozoicb.Cenozoicc.Phanerozoicd.Paleozoic 1.5 m =_____ cma 15b 0.015c 1.5d 150 do you think my poem is good please critique it What is the answer to each problem? Please hurry :)I will give Brainlest to whoever answers correctly, thank you. What type of perspective was favored by artists who painted in the international Gothic styleA.) Aerial perspectiveB.) the persons point of viewC.) liner perspectiveD.) the God's - eye view How does the sense of belonging hele todevelop agood society?write any4 points 8)How many grams are in 0.02 moles of beryllium iodide, BeI2?9)How many moles are in 68 grams of copper (II) hydroxide, Cu(OH)2?10)How many grams are in 3.3 moles of potassium sulfide, K2S?11) How many grams are in 2.3 x 10-4 moles of calcium phosphate, Ca3(PO3)2? Koalas live almost entirely on leaves from eucalyptus trees and they are native exclusively to Australia.Destruction of the Koalas' habitat will most likely lead to -F)) koalas producing moreoffspringG)) a decrease of the koalapopulationH)) the koalas becoming larger.J)) an increase of the koalapopulation. Help me solve this problem please Kinetic vs potential energy What caused the U.S war with Tripoli during the Jefferson presidency? Select ALL that apply.Tripoli was outraged at what it believed were unfair American trade practicesAmerican forces seized several North African ports.The United States refused to pay Tripoli a tribute to guarantee safe passage for American ships.Pirates from the Barbary States attacked American ships. which position represents a basic disagreement between Democrats and Republicans Why were Native Americans in Texas moved to reservations? Write an equation of the line in slope intercept form that passes through (0,4) and (-3,-8) Evan spent 20 hours doing homework last week. This week he spent 25 hours doing homework. He says that he spent 125% more time doing homework this week. Is he correct? Show your work to justify your decision. (5 points) After Jeannette gets a divorce what type of the does she choose to live a life devoted to her parents she decided to devote her life to non profit worker a life of luxury a simple life from the glass castle book 10 POINTS!!!IS IT TRUE THAT AN APPLE, POTATO, AND ONION ALL TASTE THE SAME IF YOUR NOSE IS PLUGGED??? AND IF IT IS TRUE WHAT DOES IT TASTE LIKE??? See the case 1 and 2 These are the question I will give brainliest A. If you remove a bulb from case 1 , will the other bulb still light? Explain why.B. If you remove a bulb from case 2, will the other bulb still light? Explain why C. In which circuit do you think he bulbs glow. Brighter? Explain whyPoints and brainliest