A sample of 2,500 people was asked how many cups of coffee they drink in the morning. You are given the following sample information. Cups of Coffee Frequency 0 700 1 900 2 600 3 300 2,500 Refer to Exhibit 5-7. The variance of the number of cups of coffee is _____.

Answers

Answer 1

Answer: V(X) = 0.96

Step-by-step explanation: Variance is defined as the average of the squared difference from the sample or population mean.

For a discrete frequency distribution is calculated following the steps:

1) Determine expected value or mean:

[tex]E(X)=\frac{\Sigma xf}{\Sigma f}[/tex]

[tex]E(X)=\frac{0(700)+1(900)+2(600)+3(300)}{2500}[/tex]

E(X) = 1.2

2) Multiply frequency and the squared difference of x and expected value:

[tex]f(x-E(X))^{2}[/tex]

[tex]700(0-1.2)^{2}=1008\\900(1-1.2)^{2} = 36\\600(2-1.2)^{2} = 384\\300(3-1.2)^{2} = 972[/tex]

3) Add them:

[tex]\Sigma [f(x-E(X))^{2}][/tex] = 1008 + 36 + 384 + 972 = 2400

4) Divide the sum per frequency total:

[tex]V(X)=\frac{\Sigma [f(x-E(X))^{2}]}{\Sigma f}[/tex]

[tex]V(X)=\frac{2400}{2500}[/tex]

V(X) = 0.96

The variance of the number of cups of coffee is 0.96.


Related Questions

If

Answers

Answer: If you were born in April you a amiable, and always ready to help others and a faithful lover.

Step-by-step explanation:

Help help it’s geometry I need help

Answers

Answer: X = 57.5

Step-by-step explanation:

3x - 65 + x + 15 = 180

4x - 50 = 180

4x = 230

x = 57.5

Answer:

3x-65 degrees

Step-by-step explanation:

Since the angles are vertical angles, y should equal the same value of the corresponding angle.

Can some please help me! No one has helped me out yet, please do this is you can

Answers

Answer:

Please check the explanation below.

Step-by-step explanation:

We know that a binary relation between two sets is termed as a function which associates every element of the first set to exactly one element of the second set.

In other words, in order for relation to be a function, we must make sure there must be no repetition of 'x' coordinate values, as it would violate the fundamental definition of a function.

A) (2, 5), (5, 7), (7, 9)

Here, the x-coordinates are: 2, 5, and 7

At x = 2, y = 5

At x = 5, y = 7

At x = 7, y = 9

As there is no repetition of x-coordinates.

Thus, the coordinate pairs (2, 5), (5, 7), (7, 9) represent the function.

B) (2, 3), (1, 4), (2, 8),(0, 1)

Here, the x-coordinates are: 2, 1, 2 and 0

At x = 2, y = 3

At x = 1, y = 4

At x = 2, y = 8

At x = 0, y = 1

Please observe that the x-coordinate values i.e. x=2 are repeated.

Thus, the coordinate pairs (2, 3), (1, 4), (2, 8),(0, 1) does not represent the function.

C) (4, 8), (5, 8), (6, 8)

Here, the x-coordinates are: 4,5 and 6

At x = 4, y = 8

At x = 5, y = 8

At x = 6, y = 8

As there is no repetition of x-coordinates.

Thus, the coordinate pairs (4, 8), (5, 8), (6, 8) represent the function.

Please note that it does not matter if y-values are repeated. Just remember, we can not have repeated x-values.

D) (-1, 4), (0, -1), (8, 3)

Here, the x-coordinates are: -1, 0, and 8

At x = -1, y = 4

At x = 0, y = -1

At x = 8, y = 3

As there is no repetition of x-coordinates.

Thus, the coordinate pairs (-1, 4), (0, -1), (8, 3) represent the function.

E) (1, 8), (8, 1), (1, 3)

Here, the x-coordinates are: 1, 8, and 1

At x = 1, y = 8

At x = 8, y = 1

At x = 1, y = 3

Please observe that the x-coordinate values i.e. x=1 are repeated.

Thus, the coordinate pairs (1, 8), (8, 1), (1, 3) does not represent the function.

F) (9, 0), (9, 1), (9, 2), (9, 3)

Here, the x-coordinates are: 9, 9,9 and 9

At x = 9, y = 0

At x = 9, y = 1

At x = 9, y = 2

At x = 9, y = 3

Please observe that the x-coordinate values i.e. x=9are repeated.

Thus, the coordinate pairs (9, 0), (9, 1), (9, 2), (9, 3) does not represent the function.

2/3 (x - 7) = -2

(please help I need this turned in really soon)

Answers

Answer: x=4

Step-by-step explanation:

Answer:

x = 4

Step-by-step explanation:

[tex]\frac{2}{3} (x-7)=-2\\[/tex]

[tex]\frac{2}{3} x+\frac{-14}{3} =-2[/tex]

[tex]\frac{2}{3}x=\frac{3}{8}[/tex]

[tex]x=4[/tex]

Find the domain of the vector function. (Enter your answer in interval notation.) r(t) = t − 2 t + 2 i + sin(t)j + ln(36 − t2)k

Answers

Answer:

The domain of the vector function is :  ( -6, -2) ∪ ( -2, 6)

Step-by-step explanation:

The given vector function  can be correctly expressed as:

[tex]r(t) = \dfrac{t-2}{t+2}i + sin \ tj + In(36-t^2) k[/tex]

The domain of the given function can be determined by finding the domain of each respective component.

To start with [tex]\dfrac{t-2}{t+2}[/tex]

Not defined, t = -2

Thus, the domain of the first component of the vector = [tex]( - \infty , -2) \cup ( 2, \infty )[/tex]

The 2nd component = sin t

No restriction on t

The 3rd component of the function is ㏑(36 - t²)

Let recall that natural is defined for +ve numbers,

i.e.

36 - t² > 0

(6 + t) (6 - t) > 0

Thus, it satisfies the inequality  -6 < t < 6

The third domain = (-6,6)

Overall;

The domain of the vector function is :  ( -6, -2) ∪ ( -2, 6)

Domain of a function is the set all possible inputs for that function.The domain of the given vector function is,

[tex](-6, -2) \cap (-2,6)[/tex]

What is domain?

Domain of a function is the set all possible inputs for that function.

Given information-

The vector function given in the problem is,

[tex]r(t)=\dfrac{t-1}{t+2} \hat i++sin(t)\hat j+ln(49-t^2)\hat k[/tex]

To find the domain of the above vector function, we need to find the domain of each function of vector quantity.

Lets find the domain of [tex]\hat i[/tex] first which is given by,

[tex]\dfrac{t-2}{t+2}[/tex]

This function is defined at all values except, t equals to -2 as the function is not defined at,

[tex]t=-2[/tex]

Hence the domain of component [tex]\hat i[/tex] is,

[tex](-\infty, -2) \cap (\infty,2)\\[/tex]

Lets find the domain of [tex]\hat j[/tex] first which is given by,

[tex]\sin(t)[/tex]

Two trigonometry function sine and cosine defined for all real number.

This function is defined at all real numbers. Hence the domain of component [tex]\hat j[/tex] is

Lets find the domain of [tex]\hat k[/tex] first which is given by,

[tex]\ln(36-t^2)[/tex]

Set the above argument greater than zero to find where the expression is defined.Thus,

[tex](36-t^2)>0\\(6+t)(6-t)>0[/tex]

Therefore,

The domain of it should be [tex](-6,6)[/tex]

Hence the domain of the given vector function is,

[tex](-6, -2) \cap (-2,6)[/tex]

Learn more about the domain here;

https://brainly.com/question/10197594

Can you help me with this question please by the way its not 101

Answers

Answer:

41

Step-by-step explanation:

101+38=139

180-139 = 41

Factor 16x – 12 by the GCF.

Answers

Answer:

148 i thk i did 16x-12

Step-by-step explanation:

quiz 4-1 : classifying and solving for sides/angles in triangles gina wilson (all things algebra) URGENT

Answers

Answer:

14.

[tex]x = 11[/tex]  [tex]m<B = 108[/tex]   [tex]m<C= 36[/tex]   [tex]m<D = 36[/tex]

15.

[tex]x = 4[/tex]     [tex]WX = 25[/tex]     [tex]XY = 17[/tex]     [tex]WY = 25[/tex]

Step-by-step explanation:

Solving (14):

[tex]BC = BD[/tex]

[tex]m<B = 13x - 35[/tex]

[tex]m<C = 5x - 19[/tex]

[tex]m<D = 2x + 14[/tex]

First, we solve for x.

Since sides [tex]BC = BD[/tex], then

[tex]m<C = m<D[/tex]

This is so because the theorem of ASA (Angle-Side-Angle)

So, we have:

[tex]5x - 19 = 2x + 14[/tex]

Collect Like Terms

[tex]5x - 2x = 19 + 14[/tex]

[tex]3x = 33[/tex]

Divide both sides by 3

[tex]x = 11[/tex]

Solving for m<B, m<C and m<D.

We simply substitute 11 for x in their respective expressions.

[tex]m<B = 13x - 35[/tex]

[tex]m<B = 13*11 - 35[/tex]

[tex]m<B = 143 - 35[/tex]

[tex]m<B = 108[/tex]

[tex]m<C = 5x - 19[/tex]

[tex]m<C= 5*11 - 19[/tex]

[tex]m<C= 55 - 19[/tex]

[tex]m<C= 36[/tex]

[tex]m<D = 2x + 14[/tex]

[tex]m<D = 2*11 + 14[/tex]

[tex]m<D = 22 + 14[/tex]

[tex]m<D = 36[/tex]

Solving (15):

[tex]<X = <Y[/tex]

[tex]WX = 9x - 11[/tex]

[tex]XY = 4x + 1[/tex]

[tex]WY = 7x - 3[/tex]

First, we solve for x.

Since [tex]<X = <Y[/tex], then

[tex]WX = WY[/tex]

This is so because the theorem of SAS (Side-Angle-Side)

So, we have:

[tex]9x - 11 = 7x - 3[/tex]

Collect Like Terms

[tex]9x - 7x = 11-3[/tex]

[tex]2x = 8[/tex]

Divide both sides by 2

[tex]x = 4[/tex]

Solving for WX, WY and XY

We simply substitute 4 for x in their respective expressions.

[tex]WX = 9x - 11[/tex]

[tex]WX = 9 * 4 - 11[/tex]

[tex]WX = 36 - 11[/tex]

[tex]WX = 25[/tex]

[tex]XY = 4x + 1[/tex]

[tex]XY = 4 * 4 + 1[/tex]

[tex]XY = 16 + 1[/tex]

[tex]XY = 17[/tex]

[tex]WY = 7x - 3[/tex]

[tex]WY = 7 * 4 - 3[/tex]

[tex]WY = 28 - 3[/tex]

[tex]WY = 25[/tex]

What number is equivalent to 15 and 25

Answers

Answer:

yo are you talking about like absolute value?  then it's  | -15 | and | -25 |

Step-by-step explanation:

The vertices of a triangle are P(-2, -4), Q(2, -5), and R(-1,-8). Name the vértices of the triangle after reflecting over the x-axis

Answers

Answer:

P(-2,4)

Q(2,5)

R(-1,8)

Step-by-step explanation:

The rule for reflecting points across the x-axis is to keep the x-value the same but "negate" the y-value. So, the points above are your answers.

A room 9m wide has a span roof which slopes at 34 degrees on one side and 44 degrees on the other. Find the length of the roof slopes, correct to the nearest mm

Answers

Answer:

Slope sides are;

5.07 m and 6.39 m

Step-by-step explanation:

I've attached a drawn diagram showing a triangle representing the roof slopes and I have attached it.

From the image attached, the missing angle is θ.

From sum of angles in a triangle,

θ = 180 - (44 + 34)

θ = 102°

Now, a & b represent the slopes of the roof.

Thus, using law of sines which is that;

a/sin A = b/sin B = c/sin C, we can solve as follows;

a/sin 34 = 9/sin 102

a = (9 × sin 34)/sin 102

a = (9 × 0.5512)/0.9781

a = 5.07 m

b/sin 44 = 9/sin 102

b = (9 × sin 44)/sin 102

b = (9 × 0.6947)/0.9781

b = 6.39 m

The video game store is having a 25% off sale on all video games. How much money will Sandra save if she buys a game that originally
cost $49.952

Answers

49.952 * 0.25 = 12.488
She saves $12.488

Round 154,101 to the nearest ten.

Answers

Answer:

154,100

Step-by-step explanation:

the tenth is the 0

5 or more up the score 4 or less let it rest.

what is equivalent to 9 x (78) will brainlist

Answers

The answer is 702!!!
Answer : 702

Explanation: Just multiply 78 by 9 and it gave you 702. The parentheses doesn’t mean anything in this :)!

List the number from greatest to least 3/2, 0.75,-24,-3/2

Answers

Answer:

3/2, 0.75,-3/2, -24

Step-by-step explanation:

I think that's the answer

A polynomial function has a root of -6 with multiplicity 1, a root of -2 with multiplicity 3, a root of 0 with multiplicity 2 and a root of 4 with multiplicity 3. If the function has a positive leading coefficient and is of odd degree, which statement about the graph is true?

The graph of the function is positive on (-6, -2). The graph of the function is negative on (-∞, 0). The graph of the function is positive on (-2, 4). The graph of the function is negative on (4,∞)​

Answers

9514 1404 393

Answer:

  (a)  The graph of the function is positive on (-6, -2)

Step-by-step explanation:

A function of odd degree and positive leading coefficient will be negative from -∞ to the left-most zero. Here, that zero is -6. The multiplicity of that zeros is odd (1), so the sign changes to positive at that point, and remains positive until the next odd-multiplicity zero, which is -2, with multiplicity 3.

Hence the function is positive on the interval (-6, -2), matching choice A.

Answer:

a

Step-by-step explanation:

At the Fast-Pack It shipping, the employees can unload 25 trucks in 5 hours. Which of the following is a correct unit rate for this situation? (4 points)

5 hours per truck
1 truck per hour
1 over 5. of a truck per hour
1 over 5. of an hour per truck

Answers

Answer:

five trucks per hour

Step-by-step explanation:

Solve and explain (x^2+2xy+y^2)(x+1)

A. x^3 + 2x^2y + x^2 + y^2 + xy^2

B. x^2 + 2xy+ y^2

C. x^3 + x^2 + 2x^2y + xy^2 + y^2 + 2xy

D. x^2 + y^2 + 2xy + x + 1

Answers

answer is A

x^3 + 2x^2y + x^2 + y^2 + xy^2

Answer:

answer would be C.

Step-by-step explanation:

mUsing the distributive property.

Graph y=-3x+4
Please Help

Answers

Answer:

(-2,10)

(-1,7)

(0,4)

(1,1)

(2,-2)

(3,-5)

Step-by-step explanation:

Answer:

your anwer is x=-1/3y+4/3

Step-by-step explanation:

Liza and Kelly rode their bikes everyday for five days. They each rode the same distance everyday. Lisa rode 60 miles in all and Kelly rode 25 miles in all. How many more miles per day did Lisa ride than Kelly?​

Answers

Answer:

60/5=12  25/5=5   7 more miles a day

Step-by-step explanation:

plzz mark brainiest

Can smoke please help me with this I need help I’ll give brainliest

Answers

Answer:

only one solution at x=0

Step-by-step explanation:

Write an equation of the line that passes through each pair of points (- 2, - 3), (4, 5)

Answers

Answer:

y= 4/3x -1/3

Step-by-step explanation:

Find slope: y2-y1/x2-x1 = 5-(-3)/4-(-2) = 8/6 = 4/3

Use point slope to find the equation:

y - y1 = m ( x - x1 )

y - (-3) = 4/3 ( x - (-2))

y = 4/3x + 8/3 + (-3)

y = 4/3x + 8/3 - 9/3

y= 4/3x -1/3

(Identify the type of sampling method used.) A candidate for the senate creates an automated message that calls every third listed phone number and reminds them to vote for him in the upcoming election.

Convenience Sampling
Cluster Sampling
Systematic Sampling
Stratified Sampling

Answers

Answer:

Systematic Sampling

Step-by-step explanation:

Systematic sampling is one of the types of probability sampling method. It is an advanced form of simple random sampling. In this form, from the population of members, sample members are selected randomly. In this random selection, a starting point is fixed. The sample is created when the members are selected from the fixed intervals.  

In the given excerpt, systematic sampling method has been used. Here, the sample has been created by selecting every third listed phone member. The interval has been created between in the sample size.

an angle measures 94°. what is the measure of its supplement?

Answers

Answer:

86

Step-by-step explanation:

180-94

Simplify the expression. (Use the Distributive Property)
4(2c - 2)

Answers

Answer:

4(2-2c)

Step-by-step explanation:

because you switch it around

Answer:

-1

Step-by-step explanation:

times 4 by 2c and 4 by -2

8c and -8 then you divide by each other and get -1

Simplifying radicals! Please help me & Show WORK

Answers

Answer:

Solving the radical [tex]4\sqrt{2}(-4\sqrt{15}+3\sqrt{18})[/tex] we get [tex]\mathbf{-16\sqrt{30}+72}[/tex]

Step-by-step explanation:

We need to simplify the radical: [tex]4\sqrt{2}(-4\sqrt{15}+3\sqrt{18})[/tex]

Prime factors of 18 are: 2x3x3

Replacing [tex]\sqrt{18}[/tex] with its factors

[tex]4\sqrt{2}(-4\sqrt{15}+3\sqrt{18})\\=4\sqrt{2}(-4\sqrt{15}+3\sqrt{2\times3\times3})\\=4\sqrt{2}(-4\sqrt{15}+3\sqrt{2\times3^2})[/tex]

We know that [tex]\sqrt{3^2}=3[/tex]

[tex]=4\sqrt{2}(-4\sqrt{15}+3\times3\sqrt{2})\\=4\sqrt{2}(-4\sqrt{15}+9\sqrt{2})[/tex]

Multiplying [tex]4\sqrt{2}[/tex] with terms inside the bracket

[tex]=4\sqrt{2}(-4\sqrt{15})+4\sqrt{2}( 9\sqrt{2}))\\=-16\sqrt{2}\sqrt{15}+36\sqrt{2} \sqrt{2}[/tex]

We know that [tex]\sqrt{2} \sqrt{2}=2[/tex]

[tex]=-16\sqrt{2*15}+36(2)\\=-16\sqrt{30}+72[/tex]

So, solving the radical [tex]4\sqrt{2}(-4\sqrt{15}+3\sqrt{18})[/tex] we get [tex]\mathbf{-16\sqrt{30}+72}[/tex]

easy question if your having big problem

Answers

Answer:

whats the problem

Step-by-step explanation:

Answer:

yup

Step-by-step explanation:

John has 8 coins, all of which are quarters and nickels. In all, they're worth $1.00. How many of each kind of coin does John have?

Answers

Answer:

you will need 3 quarters and 5 nickel  

Step-by-step explanation:

3 quarters is 75     and 5 nickels is 25 =1.00

Anyone know- I need help.

Answers

Answer: 5on x axis 2 on the y axis

Answer:

The answer would be (5,2)

:D Have a Great Day :D

Alexander is a stockbroker. He eams 11% commission each week Last week, he
sold $7,100 worth of stocks. How much did he make last week in commission? The averages that
same amount each week, how much did he make in commission in 2011

Answers

(A): 825

(B): 42,900

A.) is definitely 825 and B.)42,900 I got it right
Other Questions
50 words write your response to this. - `````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````Taylor is angry that her friends left for the mall without her. She knows it is her fault because she was running late today. Still, she finds she wants to call her friend and yell at them for not waiting. Write a paragraph about the ways in which Taylor can express her anger in a healthful way. Yo me ____varias veces durante la noche. (levantar) *Urgent* I WILL GIVE BRAINLIESTSelect the answer that helps conserve the most energy. O walking to school O driving a car to school Otaking the bus to school can someone help me I will mark brainliest please help Which equation could have been used to create this graph? Which question should a writer ask when revising an essay for clarity?a) Does each paragraph use objective wording to make its point?b) Does each paragraph have an easily understandable main point?c) Does each paragraph engage the audience as it makes its point?d) Does each paragraph use formal language when discussing the main point? What do microphone means Which position would a photographer typically use to make the viewer feel like an observer?from below?from the side?from above?from the front? Read this text from Part II of "R.M.S. Titanic": Aft, the frightened immigrants mill and jostle and rush for a boat. An officer's fist flies out; three shots are fired in the air, and the panic is quelled. . . . Four Chinese sneak unseen into a boat and hide in the bottom. Which kind of conflict is exemplified here? One to one function and value evanrosario11 avatarevanrosario117 minutes agoPhysicsHigh School100 Points + Brainlest PLZ HElPWhat ion would each of the following elements form?For example, a sodium atom (Na) will form a sodium ion (Na+1). You will need to list the charge of the ion. You will need to list the charge of the ion for the seven questions below.1. Beryllium (Be)2. Sulfur (S)3. Potassium (K)4. Aluminum (Al)5. Bromine (Br)6. Oxygen (O)7. Magnesium (Mg) Mae Ling earns a weekly salary of $390 plus a 5.5% commission on sales at a gift shop. How much would she make in a work week if she sold $4,600 worth of merchandise? PLEASE HELP ITS DUE IN 15 MINSS!!!!!Given the equation of a circle below, find the diameter of the circle. Use only the digits 0-9 to enter the diameter. x squared plus y squared minus 16 x plus 12 y equals 21 What is the prime factorization of 144? Be sure to show your strategy. You have a shiny metal disc that weighs 1.31 kg that you want to find out what its made of. When you put the disc into a graduated cylinder with 5L in it, you see that the water level rose by about 125 mL. You have a list of densities for various shiny metals: silver= 10.5 g/ mL, nickel= 8.9 g/mL, titanium = 4.5 g/mL, and rhodium = 10.7 g/ mL. What is the disc made of? A cube with a volume of 75 cm is dilated bya factor of 5.What is the volume of the dilated cube?Enter yOur answer in the boxcm simplify 4 - 3(-2a + 2) please! Why was this conquest a turning point in global history? What is one benefit of participating in a writing workshop, besides helping out other writers?A. It gives your teacher a break from teaching. B. It shows you how to debate and argue a point. C. It encourages you to be critical of other people.D. It helps you see what makes good writing skills. Your uncle Brian stole three t-shirts from a stand at the mall. You are upset that he made this choice, and decide to use your iPhone to secretly record a conversation with him where he admits that he did, in fact, steal the shirts. He is awaiting trial, and you bring the recording to the police station to submit it as evidence. In your state, it is illegal to use a secretly recorded conversation in a court of law. In other words, this piece of evidence is inadmissible. Do you agree with this rule? In your answer, define the exclusionary rule and doctrine of fruit of the poisonous tree, and explain how these terms apply to your situation.