PLEASE! I NEED HELP WITH MY HOMEWORK!!!!
(GEOMETRY)

The correct choice is A. Using the cofactor expansion across the first row, the determinant of the given matrix is (2)(-13) - (-3)(-5) + (3)(7) = -26 + 15 + 21 = 10.

To compute the determinant using the cofactor expansion across the first row, we multiply each element of the first row by its cofactor and sum them up. The cofactor of an element is determined by taking the determinant of the submatrix obtained by removing the row and column containing that element, and then multiplying it by (-1) raised to the power of the sum of the row and column indices.

For the given matrix:

2  2  1

-3 1  4

3  3 -1

Expanding along the first row, we have:

Det = (2)(cofactor of 2) + (2)(cofactor of 2) + (1)(cofactor of 1)

    = (2)(-13) - (-3)(-5) + (3)(7)

    = -26 + 15 + 21

    = 10.

Therefore, the correct choice is A. The determinant of the matrix, using the cofactor expansion across the first row, is 10.

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To prove that if p is an odd prime and p = a^2 * b^2 for integers a, b, then p ≡ 1 (mod 4), we can use the concept of quadratic residues and the properties of modular arithmetic.

Let's start with the given assumption that p is an odd prime and can be expressed as p = a^2 * b^2, where a and b are integers. We want to prove that p ≡ 1 (mod 4), which means p leaves a remainder of 1 when divided by 4.

We can begin by considering the possible residues of perfect squares modulo 4. When a is an even integer, a^2 ≡ 0 (mod 4) since the square of an even number is divisible by 4. Similarly, when a is an odd integer, a^2 ≡ 1 (mod 4) since the square of an odd number leaves a remainder of 1 when divided by 4.

Now, let's examine the expression p = a^2 * b^2. Since p is a prime number, it cannot be factored into smaller integers, except for 1 and itself. Therefore, both a and b must be either 1 or -1 modulo p. We can express this as:

a ≡ ±1 (mod p)

b ≡ ±1 (mod p)

Now, let's consider the value of p modulo 4:

p ≡ (a^2 * b^2) ≡ (±1)^2 * (±1)^2 ≡ 1 * 1 ≡ 1 (mod 4)

We know that a^2 ≡ 1 (mod 4) for any odd integer a. Therefore, both a^2 and b^2 ≡ 1 (mod 4). When we multiply them together, we still obtain the residue of 1 modulo 4.

Hence, we have proven that if p is an odd prime and p = a^2 * b^2 for integers a, b, then p ≡ 1 (mod 4).

To provide an explanation of the proof, we used the concept of quadratic residues and modular arithmetic. In modular arithmetic, numbers can be classified into different residue classes based on their remainders when divided by a given modulus. In this case, we focused on the modulus 4.

We observed that perfect squares, when divided by 4, can only have residues of 0 or 1. Specifically, the squares of even integers leave a remainder of 0, while the squares of odd integers leave a remainder of 1 when divided by 4.

Using this knowledge, we analyzed the expression p = a^2 * b^2, where p is an odd prime and a, b are integers. Since p is a prime, it cannot be factored into smaller integers, except for 1 and itself. Therefore, a and b must be either 1 or -1 modulo p.

By considering the possible residues of a^2 and b^2 modulo 4, we found that both a^2 and b^2 ≡ 1 (mod 4). When we multiply them together, the resulting product, p = a^2 * b^2, also leaves a remainder of 1 modulo 4.

Thus, we concluded that if p is an odd prime and p = a^2 * b^2 for integers a, b, then p ≡ 1 (mod 4).

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The measure of AB in the triangle is 15.29.

The measure of BC is 8.05.

We have,

Using sin identity.

Sin 58 = AC / AB

AB = AC / Sin 58

AB = 13 / 0.85

AB = 15.29

Now,

Using the Pythagorean theorem.

AB² = AC² + BC²

15.29² = 13² + BC²

233.78 = 169 + BC²

BC² = 233.78 - 169

BC² = 64.78

BC = 8.05

Thus,

The measure of AB is 15.29.

The measure of BC is 8.05.

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The first 3 non-zero terms only [tex]x^4 e^{-x/2} = x^4.[/tex]

We can use the Maclaurin series for the trigonometric functions and exponential function to obtain the Maclaurin series for the given functions.

Here are the solutions:

[tex]f(x) = cos(7x^4)[/tex]

The Maclaurin series for cosine is:

[tex]cos(x) = 1 - x^2/2! + x^4/4! - x^6/6! + ...[/tex]

Substituting 7x^4 for x, we get:

[tex]cos(7x^4) = 1 - (7x^4)^2/2! + (7x^4)^4/4! - (7x^4)^6/6! + .....[/tex]

Simplifying, we get:

[tex]cos(7x^4) = 1 - 49x^8/2! + 2401x^16/4! - 117649x^24/6! + ...[/tex]

The first three non-zero terms are:

[tex]cos(7x^4) ≈ 1 - 24.5x^8 + 168.1x^16 - 2042.5x^24 + ...[/tex]

f(x) = sin(-πx)

The Maclaurin series for sine is:

[tex]sin(x) = x - x^3/3! + x^5/5! - x^7/7! + ...[/tex]

Substituting -πx for x, we get:

[tex]sin(-\pi x) = -\pi x + (-\pi x)^3/3! - (-\pi x)^5/5! + (-\pi x)^7/7! -......[/tex]

Simplifying, we get:

[tex]sin(-\pix) = -\pi x + \pi ^3 x^3/3! - \pi^5 x^5/5! + \pi^7 x^7/7! - ...[/tex]

The first three non-zero terms are:

[tex]sin(-\pi x) \approx -\pi x + 5.17\pi ^3 x^3 - 10.8\pi ^5 x^5 + 14.7\pi ^7 x^7 - ...[/tex]

[tex]f(x) = tan^-1(4x)[/tex]

The Maclaurin series for the arctangent function is:

[tex]tan^-1(x) = x - x^3/3 + x^5/5 - x^7/7 + ...[/tex]

Substituting 4x for x, we get:

[tex]tan^-1(4x) = 4x - (4x)^3/3 + (4x)^5/5 - (4x)^7/7 + .....[/tex]

Simplifying, we get:

[tex]tan^-1(4x) = 4x - 64x^3/3 + 1024x^5/5 - 16384x^7/7 + ...[/tex]

The first three non-zero terms are:

[tex]tan^-1(4x) \approx 4x - 21.33x^3 + 163.84x^5 - 1866.28x^7 + ...[/tex]

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

The Maclaurin series for the exponential function is:

[tex]e^x = 1 + x + x^2/2! + x^3/3! + ...[/tex]

Substituting -x/2 for x and multiplying by[tex]x^4[/tex], we get:

[tex]x^4 e^{-x/2} = x^4 (1 - x/2 + x^2/2! - x^3/3! + ...)[/tex]

Expanding the product, we get:

[tex]x^4 e^{-x/2} = x^4.[/tex]

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a) For the sequence sin(1/n), as n -> infinity, 1/n -> 0, and sin(1/n) -> sin(0) = 0. Thus, the rate of convergence is O(1/n).

b) For the sequence sin(1/n^2), as n -> infinity, 1/n^2 -> 0, and sin(1/n^2) -> sin(0) = 0. Thus, the rate of convergence is O(1/n^2).

c) For the sequence (sin(1/n))^2, as n -> infinity, 1/n -> 0, and sin(1/n) -> sin(0) = 0. Thus, the rate of convergence is O(1/n^2).

d) For the sequence [ln(n+1) - ln(n)], we can use the mean value theorem to show that ln(n+1) - ln(n) = 1/(c_n+1) for some c_n between n and n+1. Thus, as n -> infinity, c_n -> infinity, and 1/(c_n+1) -> 0. Thus, the rate of convergence is O(1/n).

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When choosing between two unbiased estimators of a population parameter, the one with the lower standard deviation is generally preferred as it indicates that the estimator is more precise. The correct answer is option d.

In other words, the variance of the estimator is smaller, meaning that the estimator is less likely to deviate far from the true value of the population parameter.

An estimator with a larger standard deviation, on the other hand, is less precise and is more likely to produce estimates that are farther from the true value. Therefore, it is important to consider the variability of the estimators when choosing between them.

It is worth noting, however, that the standard deviation alone is not sufficient to fully compare and evaluate two estimators. Other properties such as bias, efficiency, and robustness must also be taken into account depending on the specific context and requirements of the problem at hand.

The correct answer is option d.

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The given series ∑ [tex](3n(4n^2))^2[/tex] converges.

To determine whether the series converges or diverges, we can use the limit comparison test.

The given series is ∑ [tex](3n(4n^2))^2[/tex], where n starts from 1 and goes to infinity.

Let's simplify the series first:

[tex](3n(4n^2))^2 = 9n^2 * 16n^4 = 144n^6[/tex]

Now, let's consider the series ∑ [tex]144n^6.[/tex]

To apply the limit comparison test, we need to find a known series ∑ [tex]b_n[/tex]that converges/diverges and has positive terms.

We can compare it with the series ∑ [tex]n^6.[/tex]

Taking the limit of the ratio of the nth terms of the two series, we have:

lim (n → ∞)[tex](144n^6 / n^6)[/tex] = 144

Since the limit is a finite positive number (144), we can conclude that if the series ∑ [tex]n^6[/tex] converges, then the series ∑[tex]144n^6[/tex] also converges. Similarly, if ∑ [tex]n^6[/tex] diverges, then ∑ [tex]144n^6[/tex] also diverges.

Now, we know that the series ∑ [tex]n^6[/tex] converges (it is a p-series with p = 6 > 1), therefore, by the limit comparison test, the series ∑ [tex]144n^6[/tex] also converges.

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Answer: Your answer is D. 3.5

Step-by-step explanation: 28 divided by 8 is 8.5. I learned how to divide numbers on paper in last years math class.

Hope it helped :D

Answer:

D. 3.5

Step-by-step explanation:

We just take 28 divided by 8 and get 3.5

As the sample size (n) increases, the power of the statistical test also increases.

The power of a statistical test measures the ability of the test to detect a true effect or reject a false null hypothesis. In this case, the investigator states that the power of his test at a significance level of 1% is 0.87. If the sample size (n) increases, the power of the test increases.

Increasing the sample size generally leads to an increase in the power of a statistical test. This is because a larger sample size provides more information and reduces the variability in the data. With a larger sample size, the test has a greater chance of detecting a true effect and rejecting the null hypothesis when it is false. Consequently, the power of the test increases.

In summary, as the sample size (n) increases, the power of the statistical test also increases. This is because a larger sample size enhances the test's ability to detect true effects and reject false null hypotheses, resulting in higher statistical power. Therefore, in this scenario, increasing the sample size would lead to an increase in the power of the test.

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The answer is C. Not enough information to determine.

To understand which stock should have the highest expected return, we need more information about the stocks and the market. Standard deviation and beta are risk measures but do not directly provide information about expected return.
Standard deviation measures the dispersion of a stock's returns, with a higher standard deviation indicating greater volatility. Beta measures a stock's sensitivity to market movements, with a higher beta indicating greater responsiveness to market changes.
While risk and return are often positively correlated, meaning that higher risk investments typically offer higher potential returns, we cannot determine the expected return of these stocks based solely on their standard deviation and beta values. We would need additional information about the stocks, such as their historical returns or dividend yields, as well as the overall market conditions, to make an informed decision on which stock has the highest expected return.

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The degrees of freedom for the test is (5, 48). The p-value for this F-statistic can be obtained from an F-distribution table or calculator with the appropriate degrees of freedom.

The degrees of freedom for the regression is 5 and the sum of squares for the regression is 4,001.11. Therefore, the mean square for the regression is:

MS(regression) = SS(regression) / DF(regression) = 4,001.11 / 5 = 800.22

The degrees of freedom for the residual is 48 and the sum of squares for the residual is 2,610.04. Therefore, the mean square for the residual is:

MS(residual) = SS(residual) / DF(residual) = 2,610.04 / 48 = 54.38

The F-statistic for testing the null hypothesis that all the regression coefficients are zero is:

F = MS(regression) / MS(residual) = 800.22 / 54.38 = 14.72

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The population will reach 10,000 after about 166.68 minutes.

We can use the formula for exponential growth: N = N0 * e^(rt), where N is the population at time t, N0 is the initial population, r is the growth rate, and e is Euler's number.

Let's use the first two data points to find the growth rate and initial population. We know that after 15 minutes, N = 400, so:

400 = N0 * e^(r*15)

Similarly, after 30 minutes, N = 1400, so:

1400 = N0 * e^(r*30)

Dividing the second equation by the first, we get:

3.5 = e^(r*15)

Taking the natural logarithm of both sides, we get:

ln(3.5) = r*15

So the growth rate is:

r = ln(3.5)/15

r ≈ 0.0918

Using the first equation above, we can solve for N0:

400 = N0 * e^(0.0918*15)

N0 ≈ 98.51

So the initial population was about 98.51.

The doubling period is the time it takes for the population to double in size. We can use the formula for doubling time: T = ln(2)/r, where T is the doubling time.

T = ln(2)/0.0918

T ≈ 7.56 minutes

So the doubling period is about 7.56 minutes.

To find the population after 120 minutes, we plug in t = 120:

N = 98.51 * e^(0.0918*120)

N ≈ 22601.27

So the population after 120 minutes is about 22,601.27.

To find when the population reaches 10,000, we set N = 10,000 and solve for t:

10,000 = 98.51 * e^(0.0918*t)

t = ln(10,000/98.51)/0.0918

t ≈ 166.68 minutes

So the population will reach 10,000 after about 166.68 minutes.

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The right response is option c, which states that an interval calculated in this method has a 95 percent chance of bracketing the population mean.

Because it correctly explains what a confidence interval is, choice c is the best one. A confidence interval is a set of values derived from a sample of data that, with a certain level of certainty, contains the true population parameter.

According to the 95% confidence interval, 95% of the sample means would fall between the ranges of 112.5 and 118.4 if we were to compute the means for several samples taken from the same population.

Instead of revealing the likelihood that this range contains the genuine population mean, it only indicates the likelihood that this range does.

Therefore, option c is the correct answer.

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Answer:

200 students

--------------------

40% out of 500 students taking Spanish.

Find it in number:

Therefore, the probability that x bar is between 91 and 92.5 is approximately 1.

To find the probability that the sample mean x bar is between 91 and 92.5, we need to use the central limit theorem and assume that the sample mean follows a normal distribution with mean μ = 91.7 and standard deviation σ/√n = 0.5/√25 = 0.1.

Then, we can use a standard normal distribution with mean 0 and standard deviation 1 to find the probability:

P(91 ≤ x bar ≤ 92.5) = P[(91 - 91.7)/(0.1) ≤ (x bar - 91.7)/(0.1) ≤ (92.5 - 91.7)/(0.1)]

= P[-7 ≤ Z ≤ 8] where Z is a standard normal random variable.

Using a standard normal table or a calculator, we can find that the probability is approximately 1, since the range -7 ≤ Z ≤ 8 covers almost the entire area under the standard normal distribution.

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The dimensions that require the minimum amount of material for the open-top box are:

Length = 8 inches, Width = 8 inches, Height = 4 inches.

To find the dimensions that minimize the amount of material needed, we can approach the problem by using calculus and optimization techniques. Let's denote the length of the square bottom as "x" inches and the height of the box as "h" inches. Since the volume of the box is given as 256 cubic inches, we have the equation:

Volume = Length × Width × Height = x² × h = 256.

To minimize the material used, we need to minimize the surface area of the box. The surface area consists of the bottom area (x²) and the combined areas of the four sides (4xh). Therefore, the total surface area (A) is given by the equation:

A = x² + 4xh.

We can solve for h in terms of x using the volume equation:

h = 256 / (x²).

Substituting this expression for h in terms of x into the surface area equation, we get:

A = x² + 4x(256 / (x²)).

Simplifying further, we obtain:

A = x² + 1024 / x.

To minimize A, we take the derivative of A with respect to x, set it equal to zero, and solve for x:

dA/dx = 2x - 1024 / x² = 0.

Solving this equation yields x = 8 inches. Plugging this value back into the equation for h, we find h = 4 inches.

Therefore, the dimensions that require the minimum amount of material are: Length = 8 inches, Width = 8 inches, and Height = 4 inches.

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Yes, regular octagons and equilateral triangles can form a semi-regular tessellation of the plane.

A tessellation is a repeating pattern of shapes that covers a plane without any gaps or overlaps. In a semi-regular tessellation, multiple regular polygons are used to create the pattern.

For regular octagons and equilateral triangles to form a semi-regular tessellation, they must satisfy two conditions:

Vertex Condition: The same polygons meet at each vertex.

Edge Condition: The same polygons meet along each edge.

Let's examine these conditions for regular octagons and equilateral triangles:

Regular Octagon:

Each vertex of an octagon meets three other octagons.

Each edge of an octagon meets two other octagons.

Equilateral Triangle:

Each vertex of a triangle meets six other triangles.

Each edge of a triangle meets three other triangles.

The vertex condition is satisfied because each vertex of an octagon meets three equilateral triangles, and each vertex of an equilateral triangle meets three octagons.

The edge condition is satisfied because each edge of an octagon meets two equilateral triangles, and each edge of an equilateral triangle meets three octagons.

Therefore, regular octagons and equilateral triangles can form a semi-regular tessellation of the plane.Yes, regular octagons and equilateral triangles can form a semi-regular tessellation of the plane.

A tessellation is a repeating pattern of shapes that covers a plane without any gaps or overlaps. In a semi-regular tessellation, multiple regular polygons are used to create the pattern.

For regular octagons and equilateral triangles to form a semi-regular tessellation, they must satisfy two conditions:

Vertex Condition: The same polygons meet at each vertex.

Edge Condition: The same polygons meet along each edge.

Let's examine these conditions for regular octagons and equilateral triangles:

Regular Octagon:

Each vertex of an octagon meets three other octagons.

Each edge of an octagon meets two other octagons.

Equilateral Triangle:

Each vertex of a triangle meets six other triangles.

Each edge of a triangle meets three other triangles.

The vertex condition is satisfied because each vertex of an octagon meets three equilateral triangles, and each vertex of an equilateral triangle meets three octagons.

The edge condition is satisfied because each edge of an octagon meets two equilateral triangles, and each edge of an equilateral triangle meets three octagons.

Therefore, regular octagons and equilateral triangles can form a semi-regular tessellation of the plane.

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False. A raster data model is not necessarily a better representation of reality compared to the vector model.

The statement is false. The choice between a raster data model and a vector data model depends on the specific use case and the nature of the data being represented. While raster data models are well-suited for representing continuous data, such as elevation or satellite imagery, they can be limited in accurately representing discrete objects, such as roads or buildings.

Vector data models, on the other hand, excel at representing discrete objects with precise boundaries and attributes. The accuracy and precision of points, lines, and polygons in a vector model make it a suitable choice for many applications, including cartography, urban planning, and transportation analysis. Ultimately, the choice between the two models depends on the specific requirements and characteristics of the data being represented.

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The equilibrium price and quantity of gasoline are $3.33 per gallon and 833.33 gallons respectively.

To find the equilibrium price and quantity, we need to set the demand equal to the supply:

5 - 0.002q = 0.2 + 0.004q

Solving for q, we get q = 833.33 gallons.

To find the equilibrium price, we can substitute q back into either the demand or supply equation. Using the demand equation, we get p = $3.33 per gallon.

Therefore, the equilibrium price and quantity of gasoline are $3.33 per gallon and 833.33 gallons respectively.

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Answer:

A, B, and D

Step-by-step explanation:

the simplified expression is 1 / (200[tex]x^4[/tex]).

No problem! Let's break down the expression step by step and simplify it.

The expression you provided is:

[tex](20x^{(-3)} / 10x^{(-1)})^{(-2)}[/tex]

To simplify this, we can start by simplifying the numerator and denominator separately.

Numerator:

20[tex]x^{(-3)}[/tex]

Since we have a negative exponent, we can move the term to the denominator and change the sign of the exponent:

1 / (20[tex]x^3[/tex])

Denominator:

10[tex]x^{(-1)}[/tex]

Similarly, we move the term to the numerator and change the sign of the exponent:

10x

Now, we can rewrite the original expression as:

(1 / (20[tex]x^3[/tex])) / (10x)

To divide by a fraction, we multiply by its reciprocal:

(1 / (20[tex]x^3[/tex])) * (1 / (10x))

Multiplying the numerators and the denominators, we get:

1 / (200[tex]x^4[/tex])

Finally, we have:

1 / (200[tex]x^4[/tex])

So, the simplified expression is 1 / (200[tex]x^4[/tex]).

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A month has 4 weeks, Jose's earnings for a month would be $619.8

First, let's calculate how much Jose earns in a week:

Earnings per day = $10.33/hour * 3 hours/day = $30.99/day

Weekly earnings = $30.99/day * 5 days/week = $154.95/week

Now, let's calculate the monthly earnings by multiplying the weekly earnings by the number of weeks in a month:

Monthly earnings = $154.95/week * 4 weeks/month = $619.80/month

Therefore, Jose will have $619.80 at the end of the month if he works 3 hours a day, 5 days a week, at a rate of $10.33 per hour.

At the end of the month, Jose would have earned $619.8.

As  Jose works 3 hours a day, 5 days a week, at $10.33 an hour, he would earn:

$10.33 x 3 hours a day x 5 days a week= $154.95 per week.

Since a month has 4 weeks, Jose's earnings for a month would be:

4 weeks x $154.95 per week= $619.8

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The correct option is the third one, the explicit formula for the sequence is:

aₙ = 52 - 5n

Here we have what it seems to be an arithmetic sequence:

47, 42, 37, 32, ...

We can see that the difference between each pair of consecutive terms is -5, so that is the common difference of the sequence:

42 - 47 = -5

37 - 42 = -5

32 - 37 = -5

Then the explicit formula for the arithmetic sequence is:

aₙ = a₁ + (n - 1)*d

Where a₁ is the initial value, and d is the common difference.

So the explicit formula is:

aₙ = 47 + (n - 1)*(-5)

We can simplify this to get:

aₙ = 47  - 5n + 5

aₙ = 52 - 5n

The correct option is the third one.

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Step-by-step explanation:

log2 (7) = x  

2^(log2(7) )  = 2^x

        7 = 2^x                   <======this may be what you want

Hello !

Answer:

[tex]\Large \boxed{\sf f'(x)=-\frac{7}{(x+6)^2} }[/tex]

Step-by-step explanation:

Let's remember !

Given : [tex]\sf f(x) = \frac{7}{x+6}[/tex]

We have :

Let's derivate u and v with the previous formulas:

Now we can apply the first formula !

[tex]\sf f'(x)=\frac{0\times(x+6)-7\times1}{(x+6)^2} \\\boxed{\sf f'(x)=-\frac{7}{(x+6)^2} }[/tex]

Have a nice day ;)

The expected value of this discrete probability distribution is 2.93, and the variance is 1.21.

To find the expected value of the discrete probability distribution for this four-sided fair die, we use the formula:

E(X) = Σ(xi * Pi)

where xi represents the possible outcomes of the die, and Pi represents the probability of each outcome. In this case, the possible outcomes are 1, 2, 3, and 4, with probabilities of 9/30, 4/30, 7/30, and 10/30 respectively.

Therefore, the expected value of X is:

E(X) = (1 * 9/30) + (2 * 4/30) + (3 * 7/30) + (4 * 10/30) = 2.93

To find the variance, we first need to calculate the squared deviations of each outcome from the expected value, which is given by:

[tex](xi - E(X))^2 * Pi[/tex]

We then sum up these values to get the variance:

[tex]Var(X) = Σ[(xi - E(X))^2 * Pi][/tex]

This calculation gives a variance of approximately 1.21.

Therefore, the expected value of this discrete probability distribution is 2.93, and the variance is 1.21.

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The salary of Jamal, for a month where he made no sales, will be $3,400.

The base monthly salary of Jamal is $3,400, and he gets a commission of $0.05 for every dollar in sales.

In this equation, x represents the amount of sales he makes, and y represents his total earnings.Jamal has not made any sales this month, so x will be equal to zero. To determine his salary, we will substitute x = 0 in the given equation to get:

y = 3,400 + 0.05(0)y = 3,400 + 0y = 3,400

As per the given equation, if Jamal does not make any sales, his salary will be $3,400. He earns a base monthly salary of $3,400, and his salary increases by $0.05 for every dollar of sales he makes.

This is a linear equation with a slope of $0.05, indicating that his salary will increase by $0.05 for each dollar of sales he makes.

The y-intercept is $3,400, indicating that his base monthly salary is $3,400. We can plot this line on a graph with the y-axis representing Jamal's salary and the x-axis representing the amount of sales he makes. The slope will be 0.05, and the y-intercept will be 3,400

The salary of Jamal, for a month where he made no sales, will be $3,400.

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The value for the new mean, after removing a score with a value of X = 4 from the population, is c. 66/7.

To calculate the new mean, we need to subtract the score that is removed from the original sum of scores and then divide by the new number of scores.

Given that the population originally has N = 7 scores with a mean of μ = 10, the sum of the scores is N * μ = 7 * 10 = 70.

When the score of 4 is removed, the sum of the remaining scores becomes 70 - 4 = 66. The new number of scores is N - 1 = 7 - 1 = 6.

Therefore, the new mean is 66/6 = 11.

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The equation that best represents y, the total cost for x gallons of gas is y = 2.12x.

The equation that best represents y, the total cost for x gallons of gas if Mrs. Masek recently filled her car with gas and paid $2.12 per gallon is :y = 2.12x

Explanation :Mrs. Masek recently filled her car with gas and paid $2.12 per gallon. Let x be the number of gallons filled in the car. Now, y can be calculated using the cost per gallon of gas and the number of gallons filled in the car. Total cost (y) = Cost per gallon × Number of gallons filled in the car. Substituting the given values, we have :y = 2.12x

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