Select all the expressions that are equivalent to –25 (fraction 2 over 5)
(15 – 20d).

The correct expression to use to find how many meters it is from Washington, D.C., to Baltimore is:

C. 57 x 1,000.

An expression in mathematics is a combination of numbers, variables, and/or operators that represents a mathematical relationship or quantity. It may contain constants, variables, coefficients, and mathematical operations such as addition, subtraction, multiplication, division, and exponentiation.

In the given question,

The correct expression to use to find how many meters it is from Washington, D.C., to Baltimore is:

C. 57 x 1,000

Since 1 km equals 1,000 meters, we can convert the distance of 57 km to meters by multiplying it by 1,000. This gives us:

57 km x 1,000 meters/km = 57,000 meters

Therefore, the distance from Washington, D.C., to Baltimore is 57,000 meters.

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For the given function f(x, y), there is a saddle point at (-28, 4). There are no local maximum or local minimum points.

A saddle point or minimax point is a point on the surface of the graph of a function where the slopes in orthogonal directions are all zero, but which is not a local extremum of the function.

Local maximum and minimum are the points of the functions, which give the maximum and minimum range. The local maxima and local minima can be computed by finding the derivative of the function.

The first derivative test and the second derivative test are the two important methods of finding the local maximum and local minimum.

To find the local maximum, local minimum, or saddle points of the given function f(x, y) = y^2 + 373 + 2xy - 8x + 6y^2, we need to first find the critical points by setting the first-order partial derivatives equal to zero.

∂f/∂x = 2y - 8
∂f/∂y = 2y + 2x + 12y => 2x + 14y

Now set both partial derivatives equal to zero and solve for x and y:

2y - 8 = 0 => y = 4
2x + 14y = 0 => 2x + 56 = 0 => x = -28

The critical point is (-28, 4). Now, we need to classify this point using the second-order partial derivatives:

∂²f/∂x² = 0
∂²f/∂y² = 14
∂²f/∂x∂y = ∂²f/∂y∂x = 2

Now we can use the discriminant D = (∂²f/∂x²)(∂²f/∂y²) - (∂²f/∂x∂y)^2 = (0)(14) - (2)^2 = -4. Since D < 0, the critical point is a saddle point.

So, for the given function f(x, y), there is a saddle point at (-28, 4). There are no local maximum or local minimum points.

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The children's library has 75 science books, 125 picture books, and 125 storybooks.

z = 5x/3 (5 storybooks for every 3 science books)

y = x (the same number of picture books as science books)

y + 50 = z (the library added 50 more picture books so now there are the same number of picture books as storybooks)

Now, we can substitute the equations to solve for the number of each type of book:

From equation 2, we know that y = x. So, we can rewrite equation 3 as:

x + 50 = z

Now, we can substitute equation 1 into this equation:

x + 50 = 5x/3

Multiply both sides by 3 to eliminate the fraction:

3(x + 50) = 5x

3x + 150 = 5x

Subtract 3x from both sides:

150 = 2x

Divide both sides by 2:

x = 75

So, there are 75 science books in the library. Now we can find the number of picture books (y) and storybooks (z):

y = x = 75 (75 picture books before adding 50 more)

y = 75 + 50 = 125 (125 picture books after adding 50 more)

z = 5x/3 = (5 * 75) / 3 = 375 / 3 = 125 (125 storybooks)

So, the children's library has 75 science books, 125 picture books, and 125 storybooks.

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If number 13 is directly opposite number 35, then there are 34 children between them on the circular ring (excluding 13 and 35 themselves). There are 34 + 2 = 36 children in the ring (including both 13 and 35).

The term "opposite number" typically refers to a counterpart or equivalent in a different organization, country, or field. It can also refer to a person who holds a position or has a perspective that is opposite to another person's position or perspective. In the context of diplomacy, the term "opposite number" is often used to describe the individual with whom a diplomat or government official negotiates or communicates. For example, the United States Secretary of State might have an opposite number in the Chinese Foreign Minister.

In military contexts, "opposite number" can refer to the counterpart of a military unit or officer from an opposing force in an exercise or simulation. The term can also be used in everyday conversation to describe someone who is a polar opposite to another person in personality, beliefs, or actions.

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[tex]\sqrt[4]{81} -8( \sqrt[3]{216}) +15( \sqrt[5]{32}) +\sqrt{225}[/tex] when simplified gives 0

Indices are small number that tells us how many times a term has been multiplied by itself. Indices are also the power or exponent which is raised to a number or a variable.

How to determine this

[tex]\sqrt[4]{81} -8( \sqrt[3]{216}) +15( \sqrt[5]{32}) +\sqrt{225}[/tex]

When all of then are perfect square

[tex]\sqrt[4]{81}[/tex]= 3 * 3 *3 *3

[tex]\sqrt[3]{216}[/tex] = 6 * 6 * 6

[tex]\sqrt[2]{32}[/tex] = 2 * 2 * 2 * 2 * 2

[tex]\sqrt{225}[/tex] = 15 * 15

Therefore,

3 - 8(6) + 15(2) + 15

3 - 48 + 30 + 15

By collecting like terms

3 + 30 + 15 - 48

48 - 48

= 0

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The mean is 48.47 kg, median is 49.55 kg, mode is not available, variance is 34.1 kg², standard deviation is 5.84 kg, coefficient of variation is 12.03% and IQR is 8.35 kg.

The given data shows the weight (in kg) of 24 women in a study. To analyze the data, we need to calculate various statistical measures:

I. Statistical Measures:
a) Mean = (Sum of all weights) / (Number of observations) = (1163.4) / (24) = 48.47 kg
b) Median = Middle value of the sorted data set = 49.55 kg
c) Mode = The most frequent value in the data set = No mode as there are no repeating values.
d) Variance = (Sum of squares of deviations of each value from mean) / (Number of observations) = 34.1 kg²
e) Standard deviation = Square root of variance = 5.84 kg
f) Coefficient of variation = (Standard deviation / Mean) x 100 = 12.03%
g) IQR (Interquartile range) = Q3 - Q1 = 53.025 - 44.675 = 8.35 kg

II. Box and Whisker Plot:
The box and whisker plot displays the distribution of the data. The lower and upper quartiles are represented by the bottom and top of the box respectively, and the median is represented by the line in the middle. The whiskers represent the minimum and maximum values.

III. Distribution:
The data set appears to be skewed to the right as the median is less than the mean. There are no outliers in the data, and the IQR is relatively small, indicating that the data is not too spread out. The coefficient of variation is moderate, indicating that the data has a moderate degree of variation. Overall, the data set seems to be fairly normal, with a few outliers on the right side.

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The number of days 3 3/4 bags of tortillas will last is 5 days.

To solve this problem, we need to use the concept of fractions. We know that Lucy's burrito stand uses 3/4 of a bag of tortillas every day. So, if we want to find out how many days 3 3/4 bags of tortillas will last, we need to divide 3 3/4 by 3/4.

To do this, we can convert 3 3/4 to an improper fraction, which is 15/4. Then, we can divide 15/4 by 3/4 using the following steps:

15/4 ÷ 3/4 = 15/4 x 4/3 (we flip the second fraction and multiply)
= 60/12 (we simplify by finding a common denominator of 12)
= 5

Therefore, 3 3/4 bags of tortillas will last for 5 days at Lucy's burrito stand.

In conclusion, using fractions can help us solve real-life problems such as this one involving tortillas at a burrito stand. By understanding how to convert between mixed numbers and improper fractions, and how to divide fractions, we can calculate how long a given amount of tortillas will last and make informed decisions about our business operations.

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The table that have a constant of proportionality between y and x of 12 is the first table

From the question, we have the following parameters that can be used in our computation:

The table of values

From the first table of values, we have the following readings

(x, y) = (1/2, 6), (2, 24) and (10, 120)

Using the above as a guide, we have the following:

The constant of proportionality between y and x in the graph is

k = y/x

Substitute the known values in the above equation, so, we have the following representation

k = 6/(1/2) = 24/2 = 120/10

Evaluate

k = 12 = 12 = 12

Hence, the constant of proportionality between y and x in the first table is 12

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Complete question

Which table has a constant of proportionality between y and x of 12?

x          1/2               2             10

y           6                24          120

x          1/4               3             12

y           3                60          144

x          1/3               6             9

y           4                78          117

630 calories of total calory intake of Mrs. Ramirez should be from proteins.

From the circle graph we can see that,

percentage of calories from fruits is = 15%

percentage of calories from grains is = 15%

percentage of calories from vegetables is = 25%

percentage of calories from proteins is = 35%

percentage of calories from Dairy is = 10%

Here it is also given that Mrs. Ramirez need to eat 1800 calories.

So the calories should be from proteins

= 35% of 1800 calories

= (35/100)*1800 calories

= 35*18 calories

= 630 calories.

Hence, 630 calories should be from proteins.

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The question is incomplete. The complete question will be -

Answer: 35 English Books and 63 Maths Books

Step-by-step explanation:

5:9

x:(x+28)

Cross multiplication...

9x=5x+140

9x-5x=140

4x=140

14/4 = 35 = x

English Books = x= 35

Maths Books = x+28 = 63

Answer:

100

Step-by-step explanation:

8000/80=100

8 thousands= 8000

8 tens= 80

Expert Answer, Mark AS BRAINLIEST!!!

Rylee did approximately 58.6 sit-ups.

We are given that the mean number of sit-ups is 46 and the standard deviation is 7. We are also given that Rylee's Z-score was 1.8, we can use the formula for Z-score to find how many sit-ups she did.

The formula for Z-score is [tex]Z = \frac{X-\mu}{\sigma}[/tex]

Z = Z-score

μ = mean

σ = standard deviation

X = ?

Substituting these values into the formula

1.8 = (X - 46)/7

1.8 × 7 = X - 46

X - 46 = 12.6

X = 12.6 + 46

X = 58.6

Therefore, Rylee did approximately 58.6 sit-ups.

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Answer:

-5z/v³ + 8 + 6v²z

Do you have to simplify it further or?

Step-by-step explanation:

[tex] \frac{ - 5z + 8v {}^{3} + 6v {}^{5} z}{v {}^{3} } = \frac{ - 5z}{v {}^{3} } + \frac{8v {}^{3} }{ {v}^{3} } + \frac{6v {}^{5} }{v {}^{3} } = \frac{ - 5z}{v {}^{3} } + 8 + 6v {}^{2}z[/tex]

The scale of the drawing is 1:33 1/3, because the actual size of each grid square in the kitchen floor tile is 33 1/3 times larger than its size in the drawing.

The scale of a architectural drawing represents the proportional relationship between the size of an object in the drawing and its actual size in real life.

In this case, the floor tiles in the Jackson family's kitchen are square with a length of 8 3/4 inches on each side, while each grid square in the drawing measures 1/4 inch on each side.

To determine the scale of the drawing, we need to find the ratio between the actual size of a grid square and its size in the drawing.

Using proportions, we can set up an equation to solve for the scale. Let x be the scale of the drawing, then we have:

8 3/4 inches / (1/4 inch) = x

Simplifying the left side of the equation gives us:

35 inches = x

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As per the given information in the question, we can compute that the correct option is C) 11.

According to the question:

[tex]f(x)=x^{2} -6x-4[/tex]

[tex]g(x)=5x+3[/tex]

Therefore,

[tex](f+g)(x)= f(x)+g(x) \\

          =x^{2} -6x-4+5x+3 \\

          =x^2-x-1[/tex]

Now, to find (f+g)(-3):

substituting x=-3 in the above equation

we get,

[tex](f+g)(-3)= (-3)^2-(-3)-1 \\

                         = 9+3-1 \\

                         =11[/tex]

Hence  (f+g)(-3)=11

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The statement that if a person has his own car, then there is more chances that he or she live elsewhere in the city than to live in the downtown area in the city is true statement. So, the option(a) is right answer for problem.

We have, a sample of sample size, n

= 200

The above table contains data about location of home ( that is downtown area in city, elsewhere in city, outside the city and total) and car ownership ( Yes or No ). Now, we determine probability that car ownership |downtown area in the city

= 10/70

= 1/7

probability that car ownership | elsewhere in the city = 15/70

= 3/14

Probability that car ownership | outside in the city = 35/60 = 7/12

As we see, 1/7 < 3/14 < 7/12

here probability of car ownership downtown area of city is less than probability of car ownership if lives elsewhere in the city or less than probability of car ownership if outside the city. So, statement (a) is true in this case. Also consider,

Probability that no car ownership | downtown area in the city = 60/70 = 6/7

Probability that no car ownership | elsewhere in the city = 55/70 = 11/14

Probability that no car ownership|outside the city = 25/60 = 5/12

As we see probabilities, 5/12 < 11/14 < 6/7

Here, if a person has not own car then maximum chances that he or she live in downtown area of city. So, statement (b) is false.

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Complete question:

The above figure complete the question. A local company is interested in supporting environmentally friendly initiatives such as carpooling among employees. The company surveyed all of the 200 employees at the downtown offices. Employees responded as to whether or not they own a car and to the location of the home where they live. The results are shown in the table above. Which of the following statements about a randomly chosen person from these 200 employees is true? responses

a) if the person owns a car, he or she is more likely to live elsewhere in the city than to live in the downtown area in the city.

b) if the person does not own a car, he or she is more likely to live outside the city than to live in the city (downtown area or elsewhere).

c) the person is more likely to own a car if he or she lives in the city (downtown area or elsewhere) than if he or she lives outside the city.

d) the person is more likely to live in the downtown area in the city than elsewhere in the city.

e) the person is more likely to own a car than not to own a car.

Ms. Thompson could set up either 2 rows with 164 chairs in each row or 4 rows with 82 chairs in each row.

To find the number of chairs in each row, we need to divide the total number of chairs by the number of rows. Let's start by finding the factors of 328:

1 x 328

2 x 164

4 x 82

8 x 41

Since there must be at least 2 rows and no more than 10 rows, we can eliminate the last two factor pairs. We are left with:

2 x 164

4 x 82

We can see that the first factor pair gives us 2 rows, while the second gives us 4 rows. We are told that each row has an equal number of chairs, so we need to divide the total number of chairs by the number of rows to find out how many chairs are in each row:

For 2 rows: 328 ÷ 2 = 164 chairs in each row

For 4 rows: 328 ÷ 4 = 82 chairs in each row

Your question is incomplete but most probably your full question

Ms. Thompson sets up chairs in rows for a school concert. She uses 328 chairs. She sets up at least 2 rows of chairs but not more than 10 rows of chairs. Each row has an equal number of chairs.

How many rows of chairs does Ms. Thompson set up? Enter the number in the first box.

How many chairs are in each row? Enter the number in the second box.

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(A). To plot point C so that its distance from the origin is 1, we need to find a point on the coordinate plane that is 1 unit away from the origin. One such point is (1, 0), which is located on the positive x-axis.

(B). To plot point E 4/5 closer to the origin than C, we need to find a point that is 4/5 of the distance from the origin to point C. Since point C is located 1 unit away from the origin, point E will be 4/5 of 1 unit away from the origin, or 0.8 units away.

To find the coordinates of point E, we can multiply the coordinates of point C by 0.8. If point C is (1, 0), then point E is (0.8, 0).

(C). To plot a point at the midpoint of C and E, we can use the midpoint formula, which is (x1 + x2)/2, (y1 + y2)/2.

The coordinates of point C are (1, 0) and the coordinates of point E are (0.8, 0), so the coordinates of point H are ((1 + 0.8)/2, (0 + 0)/2), or (0.9, 0). We can label this point H.

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The absolute value of x can be written in the form

x-(1/2)x=0 or |x| = (1/2)x

To write the absolute value in the form x-b=c where b is a number and c can be either a number or expression, you can use the following steps:

1. Start with the absolute value expression: |x|

2. Recall that the absolute value of a number is the distance of that number from zero on the number line. So, we can rewrite |x| as the distance between x and 0 on the number line.

3. To write this distance in the form x-b, we need to find a value for b that represents the midpoint between x and 0. That is, we need to find the number that is halfway between x and 0 on the number line.

4. The midpoint between x and 0 is given by the expression (x + 0)/2, which simplifies to x/2.

5. So, we can write the absolute value expression |x| as the distance between x and 0, which is the same as the distance between x and x/2 + x/2.

6. Simplifying this expression, we get:

|x| = |x - x/2 - x/2|

7. Rearranging terms, we get:

|x| = |(1/2)x - (1/2)x|

8. Finally, we can write the absolute value in the form x-b=c by setting b = (1/2)x and c = 0, which gives us:

|x| = |x - (1/2)x - 0| = |(1/2)x - 0|

So, the absolute value of x can be written in the form x-(1/2)x=0, or in other words:

|x| = (1/2)x

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We need to find the dimensions of a container with square base, vertical sides, and open top that will have the greatest volume using 1000ft^2 of material. The dimensions of the container with the greatest volume are 10 ft by 10 ft by 22.5 ft.

Let x be the length of one side of the square base and y be the height of the container. Then the surface area is given by

S = x^2 + 4xy = 1000

Solving for y, we get

y = (1000 - x^2)/(4x)

The volume of the container is given by

V = x^2y = x^2(1000 - x^2)/(4x) = 250x - 0.25x^3

To find the dimensions that give the greatest volume, we need to find the critical points of the volume function. Taking the derivative with respect to x, we get

dV/dx = 250 - 0.75x^2

Setting dV/dx = 0, we get

250 - 0.75x^2 = 0

Solving for x, we get

x = 10

Substituting x = 10 into the equation for y, we get

y = (1000 - 100)/(4 × 10) = 22.5

Therefore, the dimensions of the container with greatest volume are 10 ft by 10 ft by 22.5 ft.

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The profit of the company after 8 years is approximately $105,085.11.

The value of the truck after 6 months is approximately $3,677.49.

The population of the city in 1999 is approximately 1,457.66 people.

Let P(t) be the profit in year t, where t is the number of years after 1998. The initial profit in 1998 is $35,000.

The profit increases by 18% per year, which means the profit at time t is 1.18 times the profit at time t-1. Therefore, the equation to model the situation is: [tex]P(t) = 35000 * 1.18^t[/tex]

To find the profit of the company after 8 years:

[tex]P(8) = 35000 * 1.18^8[/tex] = $105,085.11

Let V(t) be the value of the truck in year t, where t is the number of years after the purchase. The initial value of the truck is $4,000.

The value depreciates at a yearly rate of 12%, which means the value at time t is 0.88 times the value at time t-1. Therefore, the equation to model the situation is: [tex]V(t) = 4000 * 0.88^t[/tex]

To find the value of the truck after 6 months (0.5 years):

[tex]V(0.5) = 4000 * 0.88^0^.^5[/tex] = $3,677.49

Let P(t) be the population of the town in year t, where t is the number of years after 1970. The initial population in 1970 is 600.

The population increases by 2.5% per year, which means the population at time t is 1.025 times the population at time t-1. Therefore, the equation to model the situation is: [tex]P(t) = 600 * 1.025^t[/tex]

To find the population of the city in 1999 (29 years after 1970):

[tex]P(29) = 600 * 1.025^2^9 = 1,457.66[/tex]

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Kelly made at least $28 in 75% of the weeks

To determine the amount Kelly made in at least 75% of the weeks she worked, we will follow these steps:

1. Arrange the weekly earnings in ascending order:

16, 18, 21, 21, 28, 28, 32, 35.

2. Calculate 75% of the total number of weeks:

0.75 x 8 = 6 weeks.

3. Identify the earning corresponding to the 6th week: 28 dollars.

So, Kelly made at least $28 in 75% of the weeks she worked.

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The derivative of y = ln[tex](9x^2-7x+4)[/tex] is y' = (18x-7) / [tex](9x^2-7x+4)[/tex].

To differentiate f(x) = ln[tex]((x^8-2)/x[/tex]), we use the chain rule and the quotient rule:

f'(x) = [[tex](x^8[/tex]-2)/x]' / (x^8-2)/x + ln[tex]((x^8-2[/tex])/x)'

[tex]= [((x^8-2)'x - (x^8-2)x') / x^2] / (x^8-2)/x + [(1/x)'(x^8-2) - (1)'x(x^8-2)/x^2][/tex]

[tex]= [(8x^7)(x) - (x^8-2)] / x^2(x^8-2)/x + [(1/x)(x^8-2)/x^2] - (1)(x^8-2)/x^2[/tex]

[tex]= [(8x^8-2-x^8+2)] / x(x^8-2) + [(x^8-2)/x^2(-x)][/tex]

[tex]= (7x^8-4) / (x^2(x^8-2)) - (x^8-2) / (x^3(x^8-2))[/tex]

Simplify to get:

[tex]f'(x) = (6x^8-4) / (x^3(x^8-2))[/tex]

Therefore, the derivative of f(x) = ln[tex]((x^8-2)/x) is f'(x) = (6x^8-4) / (x^3(x^8-2)).[/tex]

To differentiate y = ln[tex](9x^2-7x+4)[/tex], we use the chain rule:

y' =[tex][(9x^2-7x+4)' / (9x^2-7x+4)][/tex]

[tex]= [(18x-7) / (9x^2-7x+4)][/tex]

Simplify to get:

[tex]y' = (18x-7) / (9x^2-7x+4)[/tex]

Therefore, the derivative of y = [tex]ln(9x^2-7x+4) is y' = (18x-7) / (9x^2-7x+4).[/tex]

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After performing an ANOVA test on the productivity data with a 0.05 level of significance, we reject the null hypothesis and conclude that the average productivity under different programs are not the same. Ahmadi should implement the most effective program and investigate the reasons for differences.

To analyze the productivity data and determine if there are significant differences between the four programs, we can use an ANOVA (Analysis of Variance) test. The null hypothesis is that the average productivity under different programs is the same, while the alternative hypothesis is that they are not the same.

After performing the ANOVA test at a 0.05 level of significance (α = 0.05) on the provided data, if the p-value is less than 0.05, we reject the null hypothesis and conclude that the average productivity under different programs are not the same. Therefore, the correct answer is: "by the f-test since we reject the null hypothesis (p-value<0.05), average productivity under different programs are not the same."

As the statistical consultant to Ahmadi, I would advise them to implement the program(s) that showed a statistically significant increase in productivity compared to the others, and to consider further investigation and analysis to identify the reasons behind the observed differences.

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Using the cosine law, the measure of angle R is calculated as approximately: a. 44.5°.

The cosine law is expressed as follows:

cos R = [s² + q² – r²]/2sq

Given the following side lengths of triangle QRS:

Side q = 11,

Side r = 17,

Side s = 23.

Plug in the values into the cosine law formula:

cos R = [23² + 11² – 17²]/2 * 23 * 11

cos R = 361/506

Cos R = 0.7134

R = cos^(-1)(0.7134)

R ≈ 44.5°

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The total sum of all edges of the regular quadrilateral prism is 108 cm.

As we know that the base of a regular quadrilateral prism is a square, so all its sides are equal.

The edges of the base can be calculated as:

P = 4 × L

Each side of the base has a length of 8 cm. Then, put L=4,

P = 4 (8)

P = 32 cm

The edges of the top of the prism can be calculated as:

P = 4L

P = 4 (8)

P = 32 cm

The edges of the prism height can be calculated as:

P = 4h

P = 4 (11)

P = 44 cm

The total sum of all edges can be calculated as:

= 32 + 32 + 44

= 108 cm

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If 4 buses carrying 150 football fans from same school arrive at a football stadium, then the expected-value, "E(X)" is 41 and variance "Var(X)" is 99.

To find the expected value of X, we use the formula E(X) = ∑x P(X=x), where x is = possible values of X and P(X=x) = probability of X taking the value x.

Four buses have a total of 150 students, the probability that the randomly selected person is from a bus with x students is the proportion of students on that bus divided by the total number of students:

P(X=x) = (number of students on bus with x students)/(total number of students);

So, We have:

P(X=20) = 20/150 = 2/15

P(X=35) = 35/150 = 7/30

P(X=45) = 45/150 = 3/10

P(X=50) = 50/150 = 1/3

The expected-value of X is : E(X) = 20(2/15) + 35(7/30) + 45(3/10) + 50(1/3) = 41

To find the variance of X, we use the formula Var(X) = E(X²) - [E(X)]².

We already know E(X), so we need to find E(X²).

E(X²) = ∑ x² P(X=x);

So, We have:

E(X²) = 20²(2/15) + 35²(7/30) + 45²(3/10) + 50²(1/3) = 1780;

So, variance of X is : Var(X) = E(X²) - [E(X)]² = 1780 - 41² = 99.

Therefore, the expected value of X is 41 and the variance of X is 99.

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