The density curve for a continuous random variable X has which of the following properties? The probability of any event of the form X = constant is 0. The probability of any event is the area under the density curve and above the values of X that make up the event. The total area under the density curve for X must be exactly 1. All of the above

Answers

Answer 1

The total area under the density curve for X must be exactly 1.

The region below the density curve and above the values of X that make up the event is the likelihood of any event. There must be exactly one area under the density curve for all instances of X.

A Density Curve: What Is It?

The general shape of a distribution is depicted by a density curve. The percentage of all observations falling in a certain period is represented by the area under the curve and above any interval of values on the horizontal axis. A density curve's median is the location where the area to the left and right are equal.

A graph that displays probability is known as a density curve. All probabilities are represented by 100% of the curve's area under the curve. You can alternatively state that the area is equal to 1 because 100% is a decimal, which is how we typically express probabilities.

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Related Questions

I need help with question in photo

Answers

Answer:

14

Step-by-step explanation:

[tex] {x}^{2} = {4}^{2} \\ = 16\\ 4y = 4 \times - 3 \\ 4 \times - 3 = - 12 \\ 16 - - 12 =16 + 12 \\ - \times - = + \\ 16 + 12 = 28 \\ 28 \div 2 = 14[/tex]

the sum of two numbers is 55. the greater number is seventeen times the smaller number plus one. Find the numbers

Answers

Answer:

52 and 3

Step-by-step explanation:

17x+1 + 1x =55

18x+1=55

18x=54

x=3

a display at an aquarium has sea stars to wolf eels in a ratio 4 : 5. It also has 5/8 as many rockfish as sea stars. there are 40 more wolf eels than rock fish. How many sea stars are there?

Answers

The number of sea stars is 64.

What is a ratio?

Comparing two amounts of the same units and determining the ratio tells us how much of one quantity is in the other.

In general, a: b, which can be interpreted as "a is to b," is used to denote a ratio between two quantities, let's say "a" and "b."

This ratio is expressed in fraction form as a/b. We utilize the same method for further simplifying a ratio as we use for further simplifying a fraction.

According to the question,

Ratio of sea stars to wolf eels = 4:5

Number of rock fish= 5/8 (Number of sea stars)

Number of wolf eels - Number of rock fish = 40

Using the given information, we get,

Number of sea stars = 8/5 (Number of rock fish)

On simplification,

Number of wolf eels = 80

So, number of sea stars = (4/5)*80

                                          = 64

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write the equivalent of the fraction using a denominator of 52. 2/13

Answers

Answer: 8/52

2/13=x/52

(2×52)/13=x

104/13=x

8=x

x=8

8 is the equivalent of the fraction using a denominator of 52. 2/13

Equivalent fractions can be defined as fractions that may have different numerators and denominators but they represent the same value. For example, 9/12 and 6/8 are equivalent fractions because both are equal to 3/4 when simplified.

All equivalent fractions get reduced to the same fraction in their simplest form as seen in the example given above. Explore the given lesson to get a better idea of how to find equivalent fractions and how to check if the given fractions are equivalent.

        ⇒[tex]\frac{2}{13} =\frac{x}{52}[/tex]

       ⇒[tex]\frac{2(52)}{13} = x[/tex]

      ⇒[tex]x = 8[/tex]

therefore, 8 is the equivalent of the fraction using a denominator of 52. 2/13

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Here is the question in the image

Answers

The coordinates of the edges of the mini-solar cooker are (x₁, y₁) = (0, - 60) and (x₂, y₂) = (0, 60).

The distance between the two edges is 120 centimeters.

The equation for the parabolic mirror is x + 32 = (2/225) · y².

How to analyze a parabolical mini-solar cooker

Herein we must understand the geometry of the design of the mini-solar cooker to determine all needed information. The y-coordinates of the edges of the cooker are determined by Pythagorean theorem:

[tex]y = \pm \sqrt{(68\,cm)^{2}-(32\,cm)^{2}}[/tex]

y = ± 60

The coordinates of the edges of the mini-solar cooker are (x₁, y₁) = (0, - 60) and (x₂, y₂) = (0, 60). The distance between the two edges is 120 centimeters.

Lastly, the equation of the parabolic mirror can be determined based on the equation of the parabola in vertex form:

x - h = C · (y - k)²     (1)

Where:

h, k - Coordinates of the vertex

C - Vertex constant

If we know that (h, k) = (- 32, 0) and (x, y) = (0, 60), then the vertex constant of the equation of the parabola is:

0 + 32 = C · 60²

C = 2/225

Then, the equation for the parabolic mirror is x + 32 = (2/225) · y².

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Type the correct answer in the box.
Net of a triangular prism includes 3 same-sized rectangles that coincide along their width. Each rectangle has length labeled 10 centimeters and width labeled 15 centimeters. Isosceles triangle is placed above and below of second rectangle.
The surface area of the three-dimensional figure is
square centimeters.

Answers

The surface area of this three-dimensional figure is equal to 536.6 square centimeters.

How to determine the surface area?

First of all, we would determine the total area of the three rectangles by using this formula:

Total area = 3 × Length × Width

Total area = 3 × 15 × 10

Total area = 450 cm².

Next, we would determine the total area of the two triangles by using this formula:

Total area = 2 × (1/2 × b × h)

Total area = b × h

Total area = 8.66 × 10

Total area = 86.6 cm².

Surface area = 450 + 86.6

Surface area = 536.6 cm².

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Assuming a​ 1-year, money market account investment at 2.55 percent​ (APY), a ​1.11 % inflation​ rate, a 28 percent marginal tax​ bracket, and a constant ​$60000 ​balance, calculate the​ after-tax rate of​ return, the real​ return, and the total monetary return. What are the implications of this result for cash management​ decisions?
Question content area bottom
Part 1
Assuming a​ 1-year, money market account investment at 2.55 percent​ (APY), a 28 percent marginal tax​ bracket, and a constant ​$ 60000 balance the​ after-tax rate of return is

enter your response here​%. ​(Round to two decimal​ places.)

Answers

The after-tax rate of return is 1.84%, the real return is 0.721%, the total monetary return is $1530 and the implications become very challenging to grow with such a return as the taxes

Given that money market account investment at 2.55 percent​ (APY), a ​1.11 % inflation​ rate, a 28 percent marginal tax​ bracket, and a constant ​$60000 ​balance.

Cash management is the backbone of any business. Cash management ensures that the company operates according to established standards and optimizes the use of funds to avoid wasting resources. Liquidity management decisions are therefore key to preserving a company's capital and profitability.

Firstly, we will find the after-tax return rate, we get

After-tax return rate= Before tax rate of return \times ( 1 - tax rate)

After-tax rate of return = 0.0255× ( 1 - 0.28)

After-tax rate of return = 0.0255×0.72

After-tax rate of return=1.84%

Now, we will find the real return, we get

Real  return=((1+After-tax Return)/(1+inflation rate))-1

Real return=((1+0.0184)/(1+0.0111))-1

Real return=(1.0184/1.0111)-1

Real return=1.00721-1

Real return=0.721%

Furthermore, we will find the total monetary return, we get

Total monetary rate=Balance×Before tax rate of return

Total monetary rate=60000×2.55%

Total monetary rate=$1530.

The implications of this result for cash management​ decisions is that it becomes very challenging to grow with such a return as the taxes and inflation is draining the returns and leaving only with negative returns.

Hence, the after-tax rate of return is 1.84%, the real return is 0.721%, the total monetary return is $1530 and the implications become very challenging to grow with such a return as the taxes and inflation is draining the returns and leaving only with negative returns.

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Shayla enlarged a square photo by adding 10 inches to each side so it could be seen on a large poster. The area of the enlarged photo is 256 square inches. In the equation (x+10)^2=256, x represents the side measure of the original square photo. What are the dimensions of the original photo

Answers

. sorry sorrysorrysorrysorrysorrysorrysorrysorrysorrysorrysorry

Which of the following expressions is equivalent to the one shown below?
713
7⁰
OA. 720
OB. 75
O C. 76
O D. 791

Answers

Answer: Option C   [tex]\boldsymbol{7^6}[/tex]

Work Shown:

[tex]\frac{7^{13}}{7^{7}}\\\\\\7^{13-7}\\\\\\\boldsymbol{7^6}[/tex]

Subtract the exponents to get the answer. The rule is [tex]\frac{a^{b}}{a^{c}} = a^{b-c}[/tex]. This rule only works when the bases are the same.

(A^m)/(A^n) = A ^ (m-n).
(7^13)/(7^7) = 7 ^(13-7),
7^(6) = 117649

a group of mapuve CLC MLMS4 STUDENTS were questioned how they got to school.half of the students said they walk, one-third said they take a taxi,and the rest claimed they drive.calculate the number of students delivered by a car using proper fractions​

Answers

The fraction of those who were delivered by car will be 1/6.

How to calculate the fraction?

It should be noted that from the information given, the students were questioned on how they got to schoo and half of the students said they walk, one-third said they take a taxi,and the rest claimed they drive.

Therefore, the fraction of those who were delivered by car will be:

= 1 - (1/2 + 1/3)

= 1/2 - 5/6

= 1/6

In conclusion, the fraction of those who were delivered by car will be 1/6.

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Solving (-49 ÷ 7 × 3(-8)) ÷ 4+ (6 x 3) - 21 ÷ 3 gives a. 13 O b. 67 O O d. 53 c. 25​

Answers

Answer:

THE ANSWER for this IS d) 53

It’s d lol ya but it’s 53

Consider the following data set.
45 58 41 45 38 46 45 39 40 31
1.
Sort the data and find quartiles of the data set.
2.
Find the interquartile range of the data set.
3.
Find the lower fence and the upper fence for outliers.
4.
Find outliers if they exist.

Answers

Based on the dataset given, the first quartile is 38.75, and the third quartile is 45.25. This interquartile range is 6.5. The lower fence is 29 and the upper fence is 55.

What are the quartiles in the data?

Order the sets:

31, 38, 39, 40, 41, 45, 45, 45,46, 58

First quartile position:

= 1(10 + 1) / 4

= 2.75th position

= 38 + 0.75 x (39 - 38)

= 38.75

Third quartile:

= 3(10 + 1) / 4

= 8.25th position

= 45 + 0.25 x (46-45)

= 45.25

Interquartile range:

= 45.25 - 38.75

= 6.5

Upper fence:

= 45.25 + (1.5 x 6.5)

= 55

Lower fence:

= 38.75 - (1.5 x 6.5)

= 29

59 is an outlier.

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Which best describes the graph of the cubic function f(x) = x3 + x2 + x + 1?

As x increases, y increases along the entire graph.
As x increases, y increases, decreases, and then increases again.
As x increases, y decreases, increases, and then decreases again.
As x increases, y decreases along the entire graph.

Answers

Answer:

As x increases, y increases along the entire graph.

Jada is solving the equation shown below.

Negative one-half (x + 4) = 6

Which is a possible first step to begin to simplify the equation? Select two options.
Divide both sides of the equation by –2.
Subtract 4 from both sides of the equation.
Multiply both sides of the equation by –2.
Distribute –2 over (x + 4).
Distribute Negative one-half over (x + 4).

Answers

Answer:

Distribute -1/2 over (x+4)

Step-by-step explanation:

-0.5(x+4) = 6

-0.5x - 2 = 6

-0.5x = 8

x = -16

Answer:

Multiple both sides by -2 or Distribute negative one-half over (x+4)

Step-by-step explanation:

-1/2(x+4) = 6

If I multiple both sides by -2, I am clearing the fraction:

(-2)(-1/2)(x+4) = 6(-2)

x+4 = -12

x = -16

OR

-1/2(x + 4) = 6

-1/2x -2 = 6  Remember, a negative times a positive is a negative.

-x - 4 = 12 multiply both sides by 2

-x = 16

x = -16

I need answer for questions 13 please and thank you!

Answers

There are 14 yellow blocks in the box

How to determine the number of yellow blocks?

The given parameters are:

P(Red) = 1/3P(Red and Yellow) = 1/12Sample, n = 24

The number of yellow blocks is calculated as:

Yellow = (1 - P(Red) - P(Red and Yellow)) * n

So, we have:

Yellow = (1 - 1/3 - 1/12) * 24

Evaluate

Yellow = 14

Hence, there are 14 yellow blocks in the box

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Complete question

A box contains a group of 24 blocks. Some are red, some are yellow, and some are a mixture of the two colors. The probability of drawing a red block is 1/3. The probability of drawing a red and yellow block is 1/12. Determine the number of yellow blocks.

find m+n

pls help !!!

Answers

Answer:

m + n = 140

===============

Given

Two parallel lines,Included triangle between the parallel lines,Two interior angles of the triangle are m and n,Another angle of 40°.

To find

The sum of angles m and n

Solution

As per given, the missing interior angle is corresponding with 40° angle.

Since corresponding angles are equal, the third interior angle of the triangle is 40°.

Sum of three interior angles is 180°:

m + n + 40 = 180m + n = 180 - 40m + n = 140

Apply angle sum property

m+n+40=180m+n=180-40m+n=140

The answer is 140

Differentiate between different types of plane with example

Answers

Answer:

The three planes of motion are the sagittal, coronal (or frontal) and transverse planes.

Sagittal Plane: Cuts the body into left and right halves. Forward and backward movements.

Coronal (or Frontal Plane): Cuts the body into front and back halves. ...

Transverse Plane: Cuts the body into top and bottom halves.

HELP i need the answer 20 POINTS

Answers

Answer:

  y = -1/4(x +4)² +4

Step-by-step explanation:

The equation of a parabola with focus (a, b) and directrix y=d can be written using the form ...

  y = 1/(2(b-d))(x -a)² +(b+d)/2

Application

We are given (a, b) = (-4, 3) and d=5. Using these values in the above form gives the equation ...

  y = 1/(2(3-5))(x -(-4))² +(3+5)/2

  y = -1/4(x +4)² +4

General admission tickets to a play cost $18 each. Reserved seats cost $22 each. There were 20 reserved seats sold. There were 28 more general admission tickets sold than reserved seats. How much money was paid for all of the tickets put together? Complete the chart and answer the question:​

Answers

Answer:

$22 * (20) + $18 * (48) = $1304

Step-by-step explanation:

There are 20 reserved seats so it would be: $22 * 20 = $440 for all reserved seats

There are 28 general admission tickets more than reserved seats ticket so number of general admission tickets is: 20 + 28 = 48 (tickets)

Each general admission tickets cost $18, so: $18 * 48 = $864  for all general admission tickets

So the total money was paid for all of the tickets is: $440 + $864 = $1304

Match the expressions to their solutions or equivalents. Solution of 0.5 x = 0

Answers

[tex]\huge\text{Hey there!}[/tex]

[tex]\huge\textbf{Assuming that your expression is:}[/tex]

[tex]\textsf{0.5x = 0}[/tex]

[tex]\huge\textbf{If so, let's solve for the given expression:}[/tex]

[tex]\textsf{0.5x = 0}[/tex]

[tex]\huge\textbf{Divide 0.5 to both of the sides you have:}[/tex]

[tex]\mathsf{\dfrac{0.5x}{0.5} = \dfrac{0}{0.5}}[/tex]

[tex]\huge\textbf{You have to simplify the equation above:}[/tex]

[tex]\mathsf{x = \dfrac{0}{0.5}}[/tex]

[tex]\mathsf{x = 0}[/tex]

[tex]\huge\textbf{Therefore, your answer should be:}[/tex]

[tex]\huge\boxed{\mathsf{x = }\frak{0}}\huge\checkmark[/tex]

[tex]\huge\text{Good luck on your assignment \& enjoy your day!}[/tex]

~[tex]\frak{Amphitrite1040:)}[/tex]

Simplify the following expression.x-[tex]\frac{2}{3}[/tex] x[tex]\frac{6}{7}[/tex]

Answers

Keeping the bases and adding the exponents, the simplified expression is:

[tex]x^{\frac{4}{21}}[/tex]

How to solve a product of two terms with the same base and different exponents?

We keep the bases and add the exponents.

Hence:

[tex]x^{-\frac{2}{3}} \times x^{\frac{6}{7}} = x^{-\frac{2}{3} + \frac{6}{7}} = x^{\frac{-14 + 18}{21}} = x^{\frac{4}{21}}[/tex]

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Calculate the t-score for a sampling distribution mean of 10.5, a standard deviation of 1.5, and a size of 36 drawn from a population that has a mean of 10.

Answers

The t- score for a sampling distribution is 2

The t-score is the number of standard deviations from the mean in the t-distribution.

The upper and lower bounds of a confidence interval when the data are approximately normally distributed.

T-scores and confidence intervals

Confidence intervals use t-scores to calculate the upper and lower bounds of the prediction interval. The t-score used to generate the upper and lower bounds is also known as the critical t or t* value.

The t- distribution is given by

t=(x – μ) / (S / √n)

t = T – Distribution

x = sample mean

μ = population mean

S = standard deviation

n = Sample size

It is given that sampling distribution mean of 10.5, a standard deviation of 1.5, and a size of 36 drawn from a population that has a mean of 10.

We need to find the t-score for sampling distribution

t=(x – μ) / (S / √n)

Here, x= 10.5 , μ= 10, S=1.5, n=36

t = (10.5 - 10)/ (1.5 /√36)

t= 2

Hence the value of t-score is 2

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Approximately how many years will it take for the world’s population to increase to 8,252,000,000 people? Since there will be the original 100% plus an additional 2% each year, the base in the exponential equation is 1.02. Use the equation 8252=(6080)(1.02)x, where x is the number of years. Round to the nearest year.

Answers

The number of years it will take for the world’s population to increase to 8,252,000,000 people is 16

How to determine the number of years?

This implies that we calculate the value of x

The equation is given as:

8252=(6080)(1.02)^x

Divide both sides by 6080

1.36 = (1.02)^x

Take the logarithm of both sides

log(1.36) = x * log(1.02)

Divide both sides log(1.02)

x = log(1.36)/log(1.02)

Evaluate the quotient

x = 16

Hence, the number of years is 16

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If you use your office computer 20 hours per week, and do not unplug it when it is not in use, how much carbon dioxide is produced from the vampire energy used by the office computer in one year ? help (energyvampires)

Express your answer rounded to the nearest tenth of a pound of carbon dioxide.

Answers

The carbon dioxide that is produced from the vampire energy used by the office computer is 1042.8 kWh.

How to calculate the value?

Based on the information given, the number of hours that the computer is plugged on a day will be:

= 20/7

= 2.857 hours

Therefore, the power consumption in a year will be:

= 2.857 × 365

= 1042.8 kWh

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Pre Calc work, I need help with writing piece wise functions from graphs. Can anyone help? Giving brainliest

Answers

The definition of the piece-wise function is:

[tex]f(x) = 2.5x + 1, -2 \leq x \leq 2[/tex][tex]f(x) = -3, 2 < x < 6[/tex].

What is a piece-wise function?

A piece-wise function is a function that has different definitions, depending on the input.

In this problem, for inputs between -2 and 2, the function is a line that goes through (-2,-4) and (2,6). The slope is:

m = (6 - (-4))/(2 - (-2)) = 2.5.

The y-intercept is of b = 1, hence the rule is:

[tex]f(x) = 2.5x + 1, -2 \leq x \leq 2[/tex]

For x greater than 2 and less than 6, the function is constant at -3, hence the rule is:

[tex]f(x) = -3, 2 < x < 6[/tex].

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Which of the following shows the graph of y= 2e^x?

Answers

The graph of the given function, y = 2eˣ, is given below

Graph of a function

From the question, we are to determine the graph of the given function

The given function is

y = 2eˣ

The graph of y = 2eˣ is shown below

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FRACTIONS
Equivalent fractions
Fill in the blank to make the two fractions equivalent.
blank over 30=4/5

Answers

The complete fraction is 24/30=4/5

How to create an equivalent fraction?

The expression is given as:

blank over 30=4/5

Represent the blank with x.

So, we have:

x/30=4/5

Multiply both sides by 30

x = 30 * 4/5

Evaluate

x = 24

Substitute x = 24 in x/30=4/5

24/30=4/5

Hence, the complete fraction is 24/30=4/5

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I need help with this geometry question asap!

Answers

Answer: Answer C is correct, 50.9.

Which represents the reflection of f(x)=√x over the y-axis?

Answers

We are looking for the graph of [tex]y=\sqrt{-x}[/tex]. which is shown in the attached image.

Claim: A majority of adults would erase all of their personal information online if they could. A software firm survey of 576 randomly selected adults showed that 59​% of them would erase all of their personal information online if they could. Complete parts​ (a) and​ (b) below.
a. Express the original claim in symbolic form. Let the parameter represent the adults that would erase their personal information.
b. identify the null and alternate hypothesis

Answers

A) The original claim in symbolic form is; p > 0.50

B) The Null Hypothesis is;

H₀: p = 0.50

Alternative Hypothesis is;

H_a: p > 0.50

How to identify the hypothesis claim?

We are given;

Sample size; n = 576

Sample Proportion; p^ = 59% = 0.59

A) The percentage of 59% represents the proportion of a sample and thus we are making a claim about the population proportion p in the hypotheses.

We claim "most of the adults", which indicates more than 50% or 0.50. Thus, the claim in symbolic form is; p > 0.50

B) The Null Hypothesis is;

H₀: p = 0.50

Alternative Hypothesis is;

H_a: p > 0.50

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