Marie is saving $75 each week so she can buy a new laptop which costs $1200. She has already saved $125. Find the minimum number of weeks she will have to save in order to be able to make this purchase.

we need to find the probability density function (pdf) of U = Z^2, where Z is a standard normal random variable. Then we need to show that U follows a gamma distribution with parameters a = λ = 1/2 and find the value of г(1/2) which is √π.

(1) To find the pdf of U, we can use the transformation method. Let g(x) be the pdf of Z. Then, we can write U = Z^2 and solve for Z to get Z = ± √U. Taking the positive root, we have Z = √U. Now, using the change of variables formula, we can write the pdf of U as fU(u) = fZ(√u) * (du/dz), where du/dz = 2z (since Z = √U). Therefore, fU(u) = (1/√(2π)) * e^(-(√u)^2/2) * (1/(2√u)), which simplifies to fU(u) = u^(-1/2) * (1/√(2π)) * e^(-u/2).

(2) To show that U follows a gamma distribution with parameters a = λ = 1/2, we can use the fact that the pdf of a gamma distribution with these parameters is fU(u) = (1/(Γ(1/2))) * u^(1/2 - 1) * e^(-u/2). Comparing this with the pdf we obtained in part (1), we see that they are the same (up to a constant factor). Hence, we can conclude that U follows a gamma distribution with parameters a = λ = 1/2.

(3) To find the value of г(1/2), we need to evaluate the integral г (}) = √ e¯x-¹/2dx. Making the change of variables y = √2x, we can write the integral as г (}) = √(2/π) ∫₀^∞ y^(1/2 - 1) * e^(-y^2/4) dy. This is the pdf of a chi-square distribution with one degree of freedom, which is equivalent to the gamma distribution with a = 1/2 and λ = 1/2. Hence, we have г(1/2) = √π/2, and substituting this value in the pdf we obtained in part (2) gives us fU(u) = u^(-1/2) * (1/√π) * e^(-u/2).

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A 4/4 ARM will have a fixed interest rate for the first 4 years, after it will be adjusted every 4 years.

The first number in an ARM (Adjustable Rate Mortgage) indicates the number of years the interest rate will remain fixed.

The second number represents how often the interest rate will be adjusted after the initial fixed period.

A 4/4 ARM will have a fixed interest rate for the first 4 years, after  it will be adjusted every 4 years.

1/4 ARM indicates a fixed interest rate for only one year, after it will be adjusted every 4 years.

4/1 ARM indicates a fixed interest rate for the first 4 years, after it will be adjusted every year.

1/1 ARM indicates a fixed interest rate for only one year, after it will be adjusted every year.

The length of time the interest rate will be fixed is indicated by the first number in an ARM (Adjustable Rate Mortgage).

How frequently the interest rate will be modified following the initial fixed term is indicated by the second number.

For the first four years of a 4/4 ARM, the interest rate is fixed; after that, it is revised every four years.

A 1/4 ARM denotes an interest rate that is set for just one year before being changed every four years.

A 4/1 ARM has an interest rate that is set for the first four years and then adjusts annually after that.

A 1/1 ARM denotes an interest rate that is set for just one year before being modified annually after that.

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Para determinar cuántas horas debe trabajar Raquel para poder pagar cualquiera de los pares de tenis, necesitamos calcular la diferencia entre el costo de los tenis y el dinero que tiene ahorrado, y luego dividir esa cantidad por su salario por hora.

Diferencia entre el costo de los tenis y el dinero ahorrado:

Costo de los tenis: $450, $459, $479 (cualquiera de los tres)

Dinero ahorrado: $310

Diferencia = Costo de los tenis - Dinero ahorrado

Ahora, calcularemos las horas de trabajo necesarias dividiendo la diferencia entre el costo de los tenis y el dinero ahorrado por el salario por hora.

Horas de trabajo necesarias = Diferencia / Salario por hora

Por ejemplo, si consideramos el par de tenis que cuesta $450:

Diferencia = $450 - $310 = $140

Horas de trabajo necesarias = $140 / $10.50

Raquel debería trabajar aproximadamente 13.33 horas para poder pagar el par de tenis que cuesta $450.

De manera similar, se puede calcular el número de horas de trabajo necesarias para los otros pares de tenis que cuestan $459 y $479.

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a - Interpret the plots: look for patterns, constant variance, and normal distribution to assess the model's assumptions.

b- Implicit assumptions made during the test include constant variance, normal distribution of errors, and independence of observations.

c- Compare the conclusion with the finding in part (b) to assess consistency.

Using the mentioned terms. However, please note that without specific data points or information from Problems 1.27 and 8.4, I cannot provide an exact answer or numerical calculations.

a. Residuals, Yˆ, x, normal probability plot:
- Obtain residuals by subtracting the predicted Y values (Yˆ) from the actual Y values in the data set.
- Plot residuals against Yˆ and x on two separate graphs.
- Prepare a normal probability plot using the residuals.
- Interpret the plots: look for patterns, constant variance, and normal distribution to assess the model's assumptions.

b. Lack of fit, quadratic regression, α = .05, alternatives, decision rule, conclusion, assumptions:
- Perform a formal test for lack of fit, using an F-test, by comparing the full quadratic regression model with a reduced linear model.
- State the null and alternative hypotheses (H0: quadratic model is appropriate, Ha: quadratic model is not appropriate).
- Determine the decision rule: if F > critical F-value (based on α = .05 and appropriate degrees of freedom), reject H0.
- Draw a conclusion based on the F-test result.
- Implicit assumptions made during the test include constant variance, normal distribution of errors, and independence of observations.

c. Third-order model, β111, α = .05, alternatives, decision rule, conclusion:
- Fit a third-order model (Y = β0 + β1x + β11x^2 + β111x^3) to the data.
- Test the hypothesis H0: β111 = 0 (no significant contribution from the cubic term) vs. Ha: β111 ≠ 0 (cubic term is significant).
- Determine the decision rule: if the t-test statistic > critical t-value (based on α = .05 and appropriate degrees of freedom), reject H0.
- Draw a conclusion based on the t-test result.
- Compare the conclusion with the finding in part (b) to assess consistency.

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The limit as x approaches infinity of the given expression is 7/2.

In mathematics, a limit is the value that a function approaches as the input approaches some value. Limits are essential to calculus and mathematical analysis, and are used to define continuity, derivatives, and integrals.

lim t → ∞ ∫1^(t) 7x^(-3) dx

Evaluating the integral:

lim t → ∞ [-7x^(-2) / 2]_1^(t)

= lim t → ∞ [-7t^(-2) / 2 + 7 / 2]

= 7 / 2

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The volume of the scoop of ice cream is 14.137 cm³. The height of the cone must be 2.12 cm to fit all the ice cream without spilling if it melts.

Given that,The radius of the ice cream scoop = r1 = 1.5 cm

Radius of the cone = r2 = 1.5 cm.

The scoop of ice cream is in the shape of a whole sphere. Therefore,Volume of the sphere,

V1 = (4/3)πr1³

Volume of the scoop of ice cream = V1

= (4/3)π(1.5)³ cm³

= 14.137 cm³

The scoop of ice cream is sitting in a right cone.

Therefore,Volume of the cone,V2 = (1/3)πr2²h, where h is the height of the cone.We can also find the height of the cone using Pythagoras theorem.

h² = r2² + r1²h = √(r2² + r1²)

h = √(1.5² + 1.5²)

h = √(4.5)h = 2.12 cm

The height of the cone is 2.12 cm.

Therefore,Volume of the cone,

V2 = (1/3)πr2²h

V2 = (1/3)π(1.5)²(2.12) cm³

= 4.71 cm³

Total volume required to fit all the ice cream

= V1 + V2

= 14.137 + 4.71

= 18.847 cm³

Therefore, the volume of the scoop of ice cream is 14.137 cm³. The height of the cone must be 2.12 cm to fit all the ice cream without spilling if it melts.

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(a) The probability of having at least one girl is 1 - 0.0625 = 0.9375 or 93.75%.

(b) The probability that all the children will be of the same gender is 0.0625 + 0.0625 = 0.125 or 12.5%.

The probability of having at least one girl can be calculated by finding the probability of having no girls and subtracting it from 1.

Assuming that the probability of having a boy or a girl is equal (0.5), the probability of having no girls is (0.5)^4 = 0.0625.

Therefore, the probability of having at least one girl is 1 - 0.0625 = 0.9375 or 93.75%.

(b) The probability that all the children will be of the same gender is 0.0625 + 0.0625 = 0.125 or 12.5%.

The probability that all the children will be of the same gender can be calculated by finding the probability of having all boys and adding it to the probability of having all girls.

The probability of having all boys is (0.5)^4 = 0.0625, and the probability of having all girls is also 0.0625.

Therefore, the probability that all the children will be of the same gender is 0.0625 + 0.0625 = 0.125 or 12.5%.

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Answer:

y = 1250 - .22t

The number of equilibrium points for the given nonlinear system is 3.

To find the equilibrium points, we need to set both equations to zero and solve for x and y:

1. x′ = y² − xy = 0
2. y′ = x³y² − x = 0

First, let's look at equation 2. We can factor x out:

x(y²x² - 1) = 0

There are two possibilities:

a. x = 0: Substitute x = 0 in equation 1:

y² - 0 = y² = 0 => y = 0

So, we have one equilibrium point (0, 0).

b. y²x² - 1 = 0: Replacing this in equation 1:

y² - (y²x² - 1)y = 0

Factor out y:

y(y²(1 - x²) - 1) = 0

There are two more possibilities:

i. y = 0: We already considered this case (0, 0).

ii. y²(1 - x²) - 1 = 0: This equation gives us two equilibrium points: (-1, 1) and (1, 1).

Thus, the system has a total of 3 equilibrium points: (0, 0), (-1, 1), and (1, 1).

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The surface area of revolution about the x-axis over the given intervals are: 33. 8π, 34. 32π/3, 35. 2π(2+ln(2)), 36. 8π/3, 37. 64π/15, 38. 2π, 39. (32/3)π, 40. 2π.

The surface area of revolution is given by

SA = 2π ∫[0,4] x√(1+(dy/dx)²) dx

Here, y = x and dy/dx = 1.

So, SA = 2π ∫[0,4] x√2 dx = 2π[2/3 * 2√2 * 4^(3/2) - 2/3 * 2√2] = 16π/3√2.

The surface area of revolution is given by

SA = 2π ∫[0,1] (4x+3)√(1+(dy/dx)²) dx

Here, y = 4x+3 and dy/dx = 4.

So, SA = 2π ∫[0,1] (4x+3)√17 dx = 2π[(4/15)*17^(3/2) + (3/8)*17^(1/2)] = 17π(8+3√17)/30.

The surface area of revolution is given by

SA = 2π ∫[0,2] x√(1+(dy/dx)²) dx

Here, y = x³ and dy/dx = 3x².

So, SA = 2π ∫[0,2] x√(1+9x⁴) dx. This integral cannot be evaluated analytically, so we must use numerical methods to approximate the value.

The surface area of revolution is given by

SA = 2π ∫[0,4] x√(1+(dy/dx)²) dx

Here, y = x² and dy/dx = 2x.

So, SA = 2π ∫[0,4] x√(1+4x²) dx. This integral cannot be evaluated analytically, so we must use numerical methods to approximate the value.

The surface area of revolution is given by

SA = 2π ∫[0,8] y√(1+(dx/dy)²) dy

Here, x = (4-y^(2/3))^(1/2) and dx/dy = -(2/3)y^(-1/3)(4-y^(2/3))^(-1/2).

So, SA = 2π ∫[0,8] (4-y^(2/3))^(1/2)√(1+(2/3)^2y^(-2/3)(4-y^(2/3))^(-1)) dy. This integral cannot be evaluated analytically, so we must use numerical methods to approximate the value.

The surface area of revolution is given by

SA = 2π ∫[0,1] e^(-x)√(1+(dy/dx)²) dx

Here, y = e^(-x) and dy/dx = -e^(-x).

So, SA = 2π ∫[0,1] e^(-x)√(1+e^(-2x)) dx = 2π[1 - (1/2)*e^(-2)].

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Answer:

510 miles

Step-by-step explanation:

Let 'm' be the miles traveled.

    To find the charge for 'm' miles, multiply m by rate per mile.

Charge for 'm' miles = 0.15*m = 0.15m

If we add the fixed charge per week with the charge for 'm' miles, we will get the total charge.

                       Total charge = Fixed charge + charge for m miles

                                              = 190 + 0.15m

190 + 0.15m = 266.50

Subtract 190 from both sides,

          0.15m = 266.50 - 190

         0.15m  =  76.50

Divide both sides by 0.15,

                [tex]m =\dfrac{76.50}{0.15}\\\\\\m=\dfrac{7650}{15}\\\\\\m = 510 \ miles[/tex]

Mean ozone refers to the average concentration of ozone in the lower atmosphere during the time period of 13:00 to 15:00 hours at Roosevelt Island. Ozone is a pollutant that can have harmful health effects. The lower atmosphere refers to the part of the atmosphere closest to the Earth's surface.

a. When plotting histograms of ozone and temperature using SAS, the features that are seen depend on the data. The variables may or may not have roughly normal distributions.

b. When making a scatterplot with temperature on the x-axis and ozone on the y-axis, the relationship between the two variables can be described as potentially linear. There may be interesting features in the scatterplot such as clusters of data points or outliers.

c. Linear regression may not be the best choice for these data as there may be other factors that influence the relationship between temperature and ozone that are not captured by a linear model. The error terms for different days may also be correlated with each other due to common environmental factors.

d. If a linear regression is fit to the data regardless of concerns from part c, the estimates of the slope and intercept terms will give information about the relationship between temperature and ozone. The slope represents the change in ozone concentration for each degree increase in temperature, while the intercept represents the ozone concentration when the temperature is 0 degrees Fahrenheit.

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Evaluating the function, we will see that the missing values in the table are:

Here we have a table for the cubic function:

y = 5x³

To find the missing values, we need to evaluate this function in the correspondent values.

The first value is when x = -2, then we will get:

a = 5*(-2)³

a = -40

When x = 0.

b = 5*(0)³

b = 0

When x = 1:

c = 5*(1)³

c = 5

When x = 3:

d = 5*(3)³

d = 135

These are the missing values in the table.

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Let G be a group and a be an element of G such that |a| ≤ 5. We need to show that c(a) ≤ c(a3).

To prove this, consider an arbitrary element x in c(a). Then ax = xa, which implies a3x = a2(ax) = a2(xa) = (a2x)a = (ax)a2 = x(a2a) = xa, since |a| ≤ 5 implies a2a = a3 = e. Therefore, x is also in c(a3), which means that c(a) is a subset of c(a3).

Now, consider the element a = (1 2 3)(4 5 6) in S6, the symmetric group on six elements. It can be shown that |a| = 6 and c(a) = {(1 2 3)(4 5 6), (1 3 2)(4 6 5), (1 2)(4 5)(3 6), (1 3)(4 6)(2 5), (1 4)(2 5)(3 6), (1 5)(2 4)(3 6), (1 6)(2 5)(3 4), e}, while c(a3) = {(1 2 3)(4 5 6), e}. Therefore, c(a) ≠ c(a3), and we have found an example of an element a in some group such that |a| = 6 and c(a) ≠ c(a3).

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The value of "R" that gives a sum in the formula for the sum of an infinite geometric sequence is -1 < R < 1.

In an infinite geometric sequence, the sum of the terms can be found using the formula:

S = a / (1 - r),

where "S" represents the sum, "a" is the first term, and "r" is the common ratio between the terms.

For the sum to exist, the absolute value of the common ratio (|r|) must be less than 1. If |r| is greater than or equal to 1, the terms of the sequence will grow infinitely large, and the sum will not converge.

When |r| is less than 1, the sum converges to a finite value. As the common ratio approaches 1, the sum gets larger, but it never exceeds a finite limit.

Therefore, any value of R that satisfies |R| < 1 will give a sum in the formula for the sum of an infinite geometric sequence. Values of R outside this range, where |R| ≥ 1, will result in a divergent sequence with no finite sum.

It's important to note that the specific value of R will affect the magnitude and convergence rate of the sum, but as long as |R| < 1, the sum will exist.

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Answer:

The value of k that makes f(x) = 2k a probability density function on [−1, 1] is k = 1/4.

Step-by-step explanation:

For a function to be a probability density function, it must satisfy the following two conditions:

The integral of the function over its support must be equal to 1:

∫ f(x) dx = 1

The function must be non-negative on its support:

f(x) ≥ 0, for all x in the support of f(x)

Given f(x) = 2k on [−1, 1], we need to find the value of k such that f(x) is a probability density function.

Condition 2 is satisfied because f(x) = 2k ≥ 0 for all x in the support of f(x), which is [−1, 1].

To satisfy condition 1, we need:

∫ f(x) dx = ∫_{-1}^{1} 2k dx = 2k [x]_{-1}^{1} = 2k(1 - (-1)) = 4k = 1

Solving for k, we have:

4k = 1

k = 1/4

Therefore, the value of k that makes f(x) = 2k a probability density function on [−1, 1] is k = 1/4.

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Answer: North 136.81 mph

               East: 375.88 mph

Step-by-step explanation:

Hi there,

First you are going to want to set up a triangle based on the given information. You are giving a bearing for the degrees of the triangle, so the angle for the triangle you are going to solve will be 20 degrees.

You can use either Law of Sines or SOHCAHTOA to solve, but since you are setting up a right triangle I would use SOHCAHTOA. You are trying to find the vertical and horizontal components so start with sine to find the y-value. It should look like:

sin(20)=(opposite side of the given angle/400)

It will be travelling North at 136.81 mph

Similarly, we now need to find the horizontal component. Start by using cosine. It should look like

cos(20)=(side adjacent to the given angle/400)

It should be traveling East at 375.88 mph

Hope this helps.

The north component is 137.64 mi/h and the east component is 123.12 mi/h.

To find the north and east components of the velocity, we can use trigonometry.

The velocity can be divided into two components: one in the north direction and one in the east direction. The north component is given by:

North component = Velocity x sin(θ)

where θ is the angle between the velocity vector and the north direction.

Similarly, the east component is given by:

East component = Velocity x cos(θ)

where θ is the angle between the velocity vector and the east direction.

In this case, the angle between the velocity vector and the north direction is (90° - 70°) = 20° (since the direction is given as "n 70° e", which means 70° east of north). Therefore:

North component = 400 x sin(20°) = 137.64 mi/h

The angle between the velocity vector and the east direction is 70°. Therefore:

East component = 400 x cos(70°) = 123.12 mi/h

Rounding to two decimal places, the north component is 137.64 mi/h and the east component is 123.12 mi/h.

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Answer:

10 dollars

Step-by-step explanation:

The value of the triple integral is π/4.

The given function is f(x,y,z) = z(x^2 + y^2 + z^2)^(-3/2).

We need to evaluate the triple integral over the part of the ball x^2 + y^2 + z^2 ≤ 1 defined by z ≥ 0.5.

Converting to spherical coordinates, we have x = ρsinφcosθ, y = ρsinφsinθ, and z = ρcosφ. The limits of integration are ρ = 0 to 1, φ = 0 to π/3, and θ = 0 to 2π.

So the integral becomes:

∫∫∫w f(x,y,z) dv = ∫₀^¹ ∫₀^(π/3) ∫₀^(2π) f(ρsinφcosθ, ρsinφsinθ, ρcosφ) ρ^2sinφ dθ dφ dρ

Substituting the function and limits, we have:

∫∫∫w z(x^2 + y^2 + z^2)^(-3/2) dv = ∫₀^¹ ∫₀^(π/3) ∫₀^(2π) (ρcosφ)(ρ^2)sinφ dθ dφ dρ

= ∫₀^¹ ∫₀^(π/3) ∫₀^(2π) ρ^3cosφsinφ dθ dφ dρ

= 2π ∫₀^¹ ∫₀^(π/3) ρ^3cosφsinφ dφ dρ

= π/4

Hence, the value of the given triple integral is π/4.

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Using the method of substitution to solve the system of equations, the solution to the system of equations is:

x = 47/2, y = 19

We can use the method of substitution to solve the given system of equations.

From the first equation, we have:

-2y = -38

Dividing both sides by -2, we get:

y = 19

Now we can substitute this value of y into the second equation:

-2x + 3y = 10

-2x + 3(19) = 10

Simplifying and solving for x, we get:

-2x + 57 = 10

-2x = -47

x = 47/2

Therefore, the solution to the system of equations is:

x = 47/2, y = 19

The system is not dependent, so there is no need to express the solution set in terms of one of the variables.

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Okay, let's break this down step-by-step:

* The curve is y = sqrt(x) (1)

* The limits of integration are: x = 1 to x = 4 (2)

* We need to integrate y with respect to x over these limits (3)

* Substitute the curve equation (1) into the integral:

∫4 sqrt(x) dx (4)

* Integrate: (√4)3/2 - (√1)3/2 (5) = 43/2 - 13/2 (6) = 15 (7)

* The volume of a solid generated by revolving a region about an axis is:

Volume = 2*π*15 (8) = 30*π (9)

Therefore, the volume of the solid generated when the region is revolved about the y-axis is 30*π.

Let me know if you have any other questions!

The volume of the solid generated is approximately 77.74 cubic units.

To find the volume of the solid generated when the region enclosed by y=sqrt(x), x=1, x=4, and the x-axis is revolved about the y-axis, follow these steps:

Step 1: Identify the given functions and limits.

y = sqrt(x) is the function we will use, with limits x=1 and x=4.

Step 2: Set up the integral using the shell method.
Since we are revolving around the y-axis, we will use the shell method formula for volume:
V = 2 * pi * ∫[x * f(x)]dx from a to b, where f(x) is the function and [a, b] are the limits.

Step 3: Plug the function and limits into the integral.
V = 2 * pi * ∫[x * sqrt(x)]dx from 1 to 4

Step 4: Evaluate the integral.
First, rewrite the integral as:
V = 2 * pi * ∫[x^(3/2)]dx from 1 to 4

Now, find the antiderivative of x^(3/2):
Antiderivative = (2/5)x^(5/2)

Step 5: Apply the Fundamental Theorem of Calculus.
Evaluate the antiderivative at the limits 4 and 1:
(2/5)(4^(5/2)) - (2/5)(1^(5/2))

Step 6: Simplify and calculate the volume.
V = 2 * pi * [(2/5)(32 - 1)]
V = (4 * pi * 31) / 5
V ≈ 77.74 cubic units

So, The volume of the solid generated is approximately 77.74 cubic units.

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The maximum annual profit is 1,72,0000

The profit function can be found by subtracting the cost function from the revenue function:

[tex]P(x) = R(x) - C(x) = (520x - 0.02x^2) - (160x + 100,000) = -0.02x^2 + 360x - 100,000[/tex]

To find the maximum annual profit, we need to find the value of x that maximizes the profit function.

One way to do this is to find the vertex of the parabola given by the profit function.

The x-coordinate of the vertex is given by:

x = -b/2a

where a = -0.02 and b = 360.

Substituting these values, we get:

[tex]x = -360/(2\times (-0.02)) = 9,000[/tex].

Therefore, the manufacturer should make 9,000 drives to maximize annual profit.

To find the maximum profit,  we can substitute this value into the profit function:

[tex]P(9,000) = -0.02(9,000)^2 + 360(9,000) - 100,000 = $1,720,000[/tex]

Therefore, the answer is (B) $1,720,000.

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The 90% confidence interval for the population mean is (73.06, 80.94).

The closest option to this answer is d. 73.87 to 80.14

To calculate the confidence interval for the population mean, we can use the formula:

[tex]CI = \bar{x} \pm z* (\sigma /\sqrt{n} )[/tex]

where:

[tex]\bar{x}[/tex] is the sample mean

σ is the population standard deviation (unknown, so we use the sample standard deviation, s, as an estimate)

n is the sample size

z* is the critical value from the standard normal distribution corresponding to the desired level of confidence (90% in this case)

Plugging in the values we have:

CI = 77 ± 1.645 * (19/√100)

CI = 77 ± 3.94

CI = (73.06, 80.94).

Option to this answer is d. 73.87 to 80.14

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A random sample of 100 customers who visited a department store spent an average of $77 with a standard deviation of $19. The 90% confidence interval for the population mean is: a. 75.56 to 79.44.

The 90% confidence interval for the population mean is calculated using the formula:

(sample mean) +/- (critical value) * (standard error of the mean)

The critical value for a 90% confidence interval with a sample size of 100 is 1.645. The standard error of the mean is calculated by dividing the standard deviation by the square root of the sample size:

$19 / \sqrt{100} = $1.90

Plugging in the values, we get:

$77 +/- 1.645 * 1.90 = $77 +/- $3.13

So the 90% confidence interval for the population mean is from $73.87 to $80.14.

Therefore, the answer is d. 73.87 to 80.14.

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The range of prices at 32.41% is $278.38 to $321.62 (approx).

Given,

Average price = 300

Standard deviation = 23.5

Percentage to be determined = 32.41%

We have to determine the range of prices i.e.,

mean ± Z * Standard deviation,

where, Z is the number of standard deviations that the range extends on each side of the mean.

Z can be calculated by using the standard normal distribution table.

In this case, the percentage to be determined is 32.41%.

As the normal distribution is a symmetric distribution, the range can be determined on one side only.

Therefore, we need to determine Z by subtracting the percentage to be determined from 50% (as 50% of the distribution falls on either side of the mean) and dividing it by 100, as shown below.

Z = (50% - 32.41%) / 100 = 0.0841

Using the standard normal distribution table, we can find the corresponding value of Z, which is approximately 0.92.

Therefore, the range of prices at 32.41% is given by:

Mean ± Z * Standard deviation

= 300 ± 0.92 * 23.5

= 300 ± 21.62

The range of prices at 32.41% is $278.38 to $321.62 (approx).

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The scatter plot shows a linear association.

linear means: "arranged in or extending along a straight or nearly straight line." Which if you didn't notice. All the points on the graph, make up a generally straight line.

"No association" means there is no line or association with any of the points.  So, you'd pick that if the points were all over the graph in no order, line or combination; which isn't the case.  

"Negative association" is when the top of the points come from the left of the graph lowering to the right. While Positive association would be from right to left.  So, it couldn't be choice "Negative Association" since it's coming from the right to the left of the graph.

"The point  (2, 14) is an outlier."  If you didn't know, an outlier is one dot out of a whole group.  

It's just the out-of-placed kind of dot, but it's supposed to be there.  When you look at the graph, there is no dot or outlier at point (2,14) so, that's automatically out as well.

Ending with the last choice "The scatter plot shows a linear association."

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In the recipe for a fruit smoothie drink, 20% of all pieces of fruit used are strawberries.

A recipe for a fruit smoothie drink calls for strawberries and raspberries. The ratio of strawberries to raspberries in the drink is 5:20.

The ratio of strawberries to raspberries in the drink is 5:20, i.e., the total parts are 5 + 20 = 25.

The fraction representing strawberries is: 5/25 = 1/5.

Now we have to convert this fraction to percent form.

This can be done using the following formula:

Percent = (Fraction × 100)%

Therefore, the percent of all pieces of fruit used that are strawberries is:

1/5 × 100% = 20%

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The height of BC is 14 meters.

Angle BMC is approximately 37.41 degrees.

Angle AMB is approximately 52.59 degrees.

To solve the problem, we can use the properties of similar triangles.

Let's consider triangles BMC and AMB.

Height of BC:

Since triangles BMC and AMB are similar, we can set up the following proportion:

BC / AM = MC / BM

Plugging in the given values, we have:

BC / 24 = 18.3 / (24 + BC)

Cross-multiplying the equation:

BC(24 + BC) = 18.3 × 24

Expanding and rearranging the equation:

24BC + BC² = 439.2

Rearranging to quadratic form:

BC² + 24BC - 439.2 = 0

Now we can solve this quadratic equation.

Factoring the equation or using the quadratic formula, we find:

(BC - 14)(BC + 38.8) = 0

Since the height cannot be negative, BC = 14 meters.

Angle BMC:

To find the angle BMC, we can use the inverse tangent function:

tan(BMC) = BC / MC

tan(BMC) = 14 / 18.3

BMC = arctan(14 / 18.3)

Using a calculator, we find BMC ≈ 37.41 degrees.

Angle AMB:

Since angle AMB is complementary to angle BMC, we can calculate it by subtracting BMC from 90 degrees:

AMB = 90 - BMC

AMB = 90 - 37.41

AMB ≈ 52.59 degrees.

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The behavior of the sequence =⋅n. cos (n)/ (6n +2) can be described as oscillatory and convergent.

Firstly, the cosine function causes the sequence to oscillate between positive and negative values as n increases. This means that the sequence does not approach a single fixed value, but rather fluctuates around a certain point.

However, as n becomes larger, the denominator (6n + 2) dominates the sequence, causing it to converge towards zero. This can be seen by dividing both the numerator and denominator by n, which gives a limit of 0 as n approaches infinity.

Therefore, the behavior of the sequence is a combination of oscillation and convergence towards zero. While it does not approach a single fixed value, it does approach zero and does so in an oscillatory manner.

Overall, the sequence can be described as a damped oscillation that gradually decreases in amplitude as n increases. It is important to note that this behavior is specific to this particular sequence and may not be the case for other sequences with different formulas.

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The probability that only one dog is selected when two animals are drawn at random from the shelter without replacement is 16/33.

To find the probability that only one dog is selected when two animals are drawn at random from the shelter without replacement, we can follow these steps:

Determine the total number of animals in the shelter: There are 4 cats and 8 dogs, so there are 12 animals in total.
Calculate the number of ways to select two animals from the shelter: This can be done using combinations, which is represented by the formula C(n, r) = n! / (r!(n-r)!), where n is the total number of animals and r is the number of animals we want to select. In this case, n = 12 and r = 2, so C(12, 2) = 12! / (2!(12-2)!) = 66.

Determine the number of ways to select only one dog: This can be done by multiplying the number of ways to select one dog with the number of ways to select one cat. There are 8 dogs and 4 cats, so the number of ways to select only one dog is 8 * 4 = 32.
Calculate the probability: Finally, divide the number of ways to select only one dog by the total number of ways to select two animals. The probability of selecting only one dog is 32 / 66, which simplifies to 16 / 33.

So, the probability that only one dog is selected when two animals are drawn at random from the shelter without replacement is 16/33.

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The statement "Over the interval [-2, 2], function f is increasing at a faster rate than function g is decreasing" (Option d) is correct.

From the number array we can clearly see that x > 0, f(x) ↑ while x<  0 f(x) ↓.

Meanwhile in the case of g(x) it is known that 0 <x<2, gx) ↓.

[-2< x< 0, g(x) may ↓ or ↑]

Therefore, x from 0 to 2, g(x) from 6 to -16, which has gone through modification for 22 while the f(x) transforms from 0 to 26, and transformed from 26,  26 > 22.2

A crucial concept in mathematics is the function which specifies the correlation between an input set and its permitted output associates. This connection ensures that each input links to only one possible output.

Functions demonstrate their usefulness in multiple mathematical fields including calculus, linear algebra, and differential equations.

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Complete question:

Select the correct answer.

Consider functions f and g. f(x) = x^3 + 5x^2-x Which statement is true about these functions?

A. Over the interval , function f and function g are decreasing at the same rate.

B. Over the interval , function f is increasing at the same rate that function g is decreasing.

C. Over the interval , function f is decreasing at a faster rate than function g is increasing.

D. Over the interval , function f is increasing at a faster rate than function g is decreasing.

See number array on the attached image.