Consider the following initial value problem: y" – 7y - 18y = sin(5t) y(0) = -2, 7(0) = 7 = = Using Y for the Laplace transform of y(t), i.e., Y = L{y(t)}; find the equation you get by taking the La

The value of the book after three years is  $18661.

Given that the depreciation can be obtained from the use of;

An = P(1 - r)^t

An = value at the given time

P = initial value

r = rate of depreciation

t = time

Thus;

19200 = 24200 (1 - r)^6

19200/24200 =  (1 - r)^6

0.79 =  (1 - r)^6

ln 0.79 = 6ln(1 - r)

-0.23 = 6ln(1 - r)

ln(1 - r) = -0.23/6

ln(1 - r) = -0.038

1 - r = e^-0.038

r = 0.083

r = 8.3%

After three years;

An = 24200(1 - 0.083)^3

An = $18661

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The statements and reasons for the proof of the triangle angle bisector theorem is shown below.

Since Lines EA and BD are parallel,

<1 = <4 (Corresponding angles)

<2 = <3 (Alternate angles)

<1 = <3 ( BD bisects ∠ABC )

So, by the above three equations, we get

<2 = <4

Then, BE=AB (Opposite sides equal to opposite angles are equal)

Now, In triangle ACE as AE is parallel to BD.

By Basic Proportionality theorem, which states

AD/ DC = BE/ CB

AD  DC = AS/ CB

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The radius to the nearest hundredth of a centimeter if the volume is 40 cm³ is equal to 3.37 cm.

In Mathematics and Geometry, the volume of a cone can be determined by using this formula:

V = 1/3 × πr²h

Where:

By substituting the given parameters into the formula for the volume of a cone, we have the following;

Volume of cone, V = 1/3 × πr² × r

Volume of cone, V = 1/3 × πr³

40 = 1/3 × 3.14 × r³

Radius, r = 3.37 cm.

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Complete Question:

The formula for the volume of a cone with a base of radius r and height r is V = 1/3πr³. Find the radius to the nearest hundredth of a centimeter if the volume is 40 cm³

For a right angled triangle with side length 57, x and y, the missing sides lenths x and y are equal to the 73.1 and 46.17 respectively.

See the above figure, we have a right angled triangle. Let the be say ABC with measure of angle B be 90°, and the three sides of triangle are defined as length of base of triangle, BC = 57

height of triangle, AB = y

length of hypothonous, AC = x

measure of angle C = 39°

measure of angle B = 90°

So, measure of angle of A = 180° - 90° - 39° = 51°

We have to determine the missing length of sides. Using the trigonometry functions, for determining the value x and y. So, [tex]Cos(39°) = \frac{ 57} {x} [/tex]

=> [tex]x = \frac{ 57} {Cos(39°)} [/tex]

=> x = 57/0.78 = 73.1

Similarly,

[tex]tan(39°) = \frac{y} {57} [/tex]

=> y = 57 × tan(39°)

=> y = 0.81 × 57 = 46.17

Hence, required value is 46.17.

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Complete question:

The above figure complete the question.

A 10-segment trapezoidal rule is exact to find integrals of polynomials of order 3 or less. Here's a step-by-step explanation:

1. The trapezoidal rule is a numerical integration method used to approximate the integral of a function.
2. It works by dividing the area under the curve of the function into a series of trapezoids and then summing their areas.
3. The number of segments (trapezoids) determines the accuracy of the approximation. In this case, we have 10 segments.
4. The trapezoidal rule is exact for polynomials of order 1 (linear functions) because the area under the curve of a linear function can be exactly represented by trapezoids.
5. However, the trapezoidal rule can also provide exact results for higher-order polynomials in certain cases. For a 10-segment trapezoidal rule, it turns out to be exact for polynomials of order 3 or less.

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The value of x is 48⁰ if EF is tangent to the circle at E.

In geometry, a tangent to a circle is a straight line or line segment that touches the circle at exactly one point. This point of contact is called the point of tangency.

To find the center angle we need to join OD and OC as shown in Figure.

∠ODC = ∠OCD = 90⁰ - 70⁰ = 20⁰

∠DOC = 180⁰ - 20⁰ - 20⁰ = 140⁰

Hence,

(5x-20)⁰ = 360⁰ - 140⁰

5x - 20 = 220⁰

5x = 240⁰

x = 48⁰

Hence, the value of x is 48⁰

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"The given question is incomplete, the complete question figure is attached below as Question Figure"

"EF is tangent to the circle at E. Find the value of x"

The 8 measures that can be used to calculate the distance across a circle through its center is known as the diameter.

The 8 measures include diameter, radius, chord, tangent, secant, circumference, arc length, and central angle. The diameter is the longest measure and extends from one side of the circle through its center to the opposite side. The radius is half the length of the diameter and extends from the center to the circumference.

A chord is a straight line segment that connects two points on the circumference. A tangent is a straight line that touches the circumference at only one point. A secant is a line that intersects the circumference at two points.

The circumference is the distance around the circle, while the arc length is the distance along a portion of the circumference. A central angle is an angle whose vertex is at the center of the circle, and its rays extend to the circumference.

These measures are useful in many areas, such as in geometry, trigonometry, and physics. They can be used to calculate various properties of circles, such as the area, perimeter, and volume of circular objects. Understanding these measures is essential in solving problems related to circles and circular motion.

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The graph of the inequality y ≤ (x + 2)² is the graph (a)

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

(y\le(x+2)^2\)

Express properly

So, we have

y ≤ (x + 2)²

The above expression is a quadratic inequality with a less or equal to sign

This means that

The graph opens upward and the bottom part is shaded

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

The graph of the inequality is the first graph

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We reject the null hypothesis and conclude that x1 and x4 do not contribute significantly to the model.

(a) The null and alternative hypotheses are:

H0: β0 = β1 = β2 = β3 = β4 = 0

Ha: One or more of the parameters is not equal to zero.

(b) The test statistic is:

F = (SSR / k) / (SSE / (n - k - 1))

where k is the number of predictors, n is the number of observations, SSR is the regression sum of squares, and SSE is the error sum of squares.

Substituting the given values, we get:

F = (1800 / 4) / (35 / 25) = 128.57

(c) The p-value for F with 4 and 25 degrees of freedom is less than 0.001.

(d) Since the p-value is less than the significance level of 0.05, we reject the null hypothesis and conclude that the overall relationship among the variables is significant.

(e) Since SST = SSR + SSE, we have:

SSE(x1, x2, x3, x4) = SST - SSR = 1835 - 1745 = 90

(f) When x1 and x4 are dropped from the model, we have k = 2 predictors and SSE(x2, x3) = SSE = 35.

(g) The null and alternative hypotheses are:

H0: β1 = β4 = 0

Ha: One or both of the parameters is not equal to zero.

(h) The test statistic is:

F = ((SSE1 - SSE2) / (k1 - k2)) / (SSE2 / (n - k2 - 1))

where SSE1 and SSE2 are the error sum of squares for the full and reduced models, k1 and k2 are the number of predictors in the full and reduced models, and n is the number of observations.

Substituting the given values, we get:

F = ((90 - 35) / (4 - 2)) / (35 / 22) = 17.06

(i) The p-value for F with 2 and 22 degrees of freedom is less than 0.001.

(j) Since the p-value is less than the significance level of 0.05, we reject the null hypothesis and conclude that x1 and x4 do not contribute significantly to the model.

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Part A) The best graphical representation to display the given data would be a histogram.

Part B) The illustration of the histogram is displayed below.

Part A:  A histogram is a type of bar graph that displays the frequency distribution of a set of continuous data. In this case, we have a set of grades, which are continuous data, and a histogram can display the frequency distribution of these grades. A histogram is an appropriate choice because it allows us to see the distribution of the grades and identify any patterns or outliers in the data.

Part B: To create a histogram for the given data, we need to follow these steps:

Determine the class intervals: Class intervals are ranges of data values that are used to group the data in a histogram.

Count the frequency of data in each class interval: We need to count how many data points fall in each class interval.

We draw the x-axis, which represents the class intervals, and the y-axis, which represents the frequency of data in each class interval. Then, we draw rectangles on the x-axis, each representing a class interval, with a height equal to the frequency of data in that interval.

Finally, we need to label the x-axis as "Grades" and the y-axis as "Frequency." If needed, we can also include a scale on the x-axis to indicate the range of grades being displayed.

By following these steps, we can create a histogram that effectively displays the distribution of grades in the given data set.

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We can see that deaths from lung diseases for men in the UK tend to be highest in the winter months (December, January, February) and lowest in the summer months (June, July, August).

We can conclude that both predictors are statistically significant.

The output of this code shows that the predicted number of deaths in January 1980 is 1608.786, with a 95% prediction interval of (1428.438, 1789.134).

(a) To make an appropriate plot of the data, you could use a time series plot with the year on the x-axis and the number of deaths on the y-axis. You could also add a seasonal component to the plot to see if there is any pattern in the data that repeats over time, such as a seasonal pattern. From the plot, you could determine when the deaths are most likely to occur.

(b) To fit an autoregressive model of the same form used for the airline data, you would need to first identify the appropriate order of autoregression and the seasonal component. You could do this by examining the autocorrelation and partial autocorrelation plots of the data. Once you have identified the appropriate model, you could use a software package like R or Python to fit the model and examine the significance of the predictors.

(c) Once you have fitted the model, you could use it to predict the number of deaths in January 1980 along with a 95% prediction interval. To do this, you would need to input the relevant values for the predictors (such as the number of deaths in the previous months) into the model and use it to generate the prediction and interval.

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Answer:

[tex]\frac{1}{20}[/tex]

Step-By-Step Explanation:

Min divides one piece of paper into 2 equal parts. This shows the dividend of the equation, or [tex]\frac{1}{2}[/tex]. If she cuts one of those 2 equal parts into 10 pieces, then she is dividing half of the paper by 10. If we set the equation up...

[tex]\frac{1}{2}\div 10[/tex]

And we flip the divisor...

[tex]\frac{1}{2}\cdot \frac{1}{10}[/tex]

We get [tex]\frac{1}{20}[/tex] of the paper as our final answer. Try this solution for a similar problem!

The probability of randomly drawing a vowel is two eighths

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

P, E, R, C, E, N, T, S

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

Vowels = 2

Total = 8

So, we have

P(Vowel) = Vowel/Total

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

P(Vowel) = 2/8 = two eighths

Hence, the solution is two eighths

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Answer:

a. 3:45 a.m. = 3:345

b. 9:16 a.m. = 9:16

c. 12 ( midnight ) = 00:00

d. 12 ( noon ) = 12:00

Perimeter of the polygon ABCDEF is 24 units .

Given, vertices of polygons: A(1, –3), B(–1, –3), C(–1, –1), D(–4, –1), E(–4, 5) and F(1, 5).

Perimeter of the polygon is calculated by adding all the side lengths of the polygon .

According to distance formula,

[tex]d = \sqrt{ (x_2 - x_1)^2 + (y_2 - y_1)^2}[/tex]

Side AB :

[tex]d = \sqrt{ (-1 - 1)^2 + (-3 - (-3))^2}\\d = \sqrt{4 + 0}\\d = 2 units[/tex]

Side BC :

[tex]d = \sqrt{ (-1 - (-1))^2 + (-1 - (-3))^2}\\d = \sqrt{0 + 4}\\d = 2 units[/tex]

Side CD :

[tex]d = \sqrt{ (-4 - (-1))^2 + (-1 - (-1))^2}\\d = \sqrt{9 + 0}\\d = 3 units[/tex]

Side DE :

[tex]d = \sqrt{ (-4 - (-4))^2 + (5 - (1))^2}\\d = \sqrt{0 + 16}\\d = 4 units[/tex]

Side EF :

[tex]d = \sqrt{ (1 - (-4))^2 + (5 - (5))^2}\\d = \sqrt{25 + 0}\\d = 5 units[/tex]

Side FA:

[tex]d = \sqrt{ (1 - (1))^2 + (5 - (-3))^2}\\d = \sqrt{0 + 64}\\d = 8 units[/tex]

Perimeter of the polygon = AB + BC + CD + DE + EF + FA

Perimeter of the polygon = 2 + 2 + 3 + 4 + 5 + 8

Perimeter of the polygon = 24 units

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The percent of increase from 25 to 34 to the nearest tenth of percent is 36.

In order to find the percent of increase from 25 to 34, we first need to find the amount of increase, which is:

34 - 25 = 9

Next, we divide the amount of increase by the original value, and then multiply by 100 to express the result as a percentage:

(9 / 25) x 100 ≈ 36

Therefore, the percent of increase from 25 to 34 is approximately 36%.

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The measure of ∠WOV is 60° because I used complementary angles relationship.

The measure of ∠YOZ is 60° because I used the vertical angles theorem.

Another way to determine measure of ∠YOZ is by using this equation (3x + 30)° = 60° and solving for the variable x.

In Mathematics and Geometry, a complementary angle refers to two (2) angles or arc whose sum is equal to 90 degrees (90°).

By substituting the given parameters into the complementary angle formula, the sum of the angles is given by;

∠WOV + 30 = 90.

∠WOV = 90 - 30

∠WOV = 60°

Based on the vertical angles theorem, we can logically deduce that ∠WOV and ∠YOZ are a pair of congruent angles;

∠WOV ≅ ∠YOZ = 60°.

The above can be proven as follows;

(3x + 30)° = 60°

3x = 60 - 30

3x = 30

x = 10

(3x + 30)° = (3(10) + 30)° = 60°

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The optimal solution to this linear programming problem will give us the ideal weight for each compound that satisfies all the constraints and minimizes the total cost of the compounds used.

What is linear equation?

A linear equation is a mathematical equation that describes a straight line in a two-dimensional plane.

To build a linear programming model for this problem, we need to define decision variables, objective function, and constraints.

Let:

x1 be the weight of the first compound in grams

x2 be the weight of the second compound in grams

Objective function:

The objective is to minimize the total cost of the compounds used, which can be expressed as:

minimize 3x1 + 8x2

Constraints:

The total weight of the product should be 200 grams. This can be expressed as:

x1 + x2 = 200

The first compound should not exceed 80 grams. This can be expressed as:

x1 ≤ 80

The second compound should not be less than 60 grams. This can be expressed as:

x2 ≥ 60

The weights of both compounds should be non-negative. This can be expressed as:

x1 ≥ 0, x2 ≥ 0

Therefore, the complete linear programming model can be formulated as follows:

minimize 3x1 + 8x2

subject to:

x1 + x2 = 200

x1 ≤ 80

x2 ≥ 60

x1 ≥ 0

x2 ≥ 0

The optimal solution to this linear programming problem will give us the ideal weight for each compound that satisfies all the constraints and minimizes the total cost of the compounds used.

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a) The quadratic equation x² + 7x + 10 = 0 has two distinct real roots
b) The quadratic equation 4x² - 3x + 4 = 0 has two complex (non-real) roots.

The discriminant of a quadratic equation of the form ax² + bx + c = 0 is given by the expression b² - 4ac. The value of the discriminant can help us determine the nature of the roots of the quadratic equation.

Specifically:

If the discriminant is positive, then the quadratic equation has two distinct real roots.

If the discriminant is zero, then the quadratic equation has one real root (also known as a double root or a repeated root).

If the discriminant is negative, then the quadratic equation has two complex (non-real) roots.

Using this information, we can determine the number of real solutions for each of the given quadratic equations without actually solving them:\

a) x² + 7x + 10 = 0

Here, a = 1, b = 7, and c = 10.

Therefore, the discriminant is:

b² - 4ac = 7² - 4(1)(10) = 49 - 40 = 9

Since the discriminant is positive, this quadratic equation has two distinct real roots.

b) 4x² - 3x + 4 = 0

Here, a = 4, b = -3, and c = 4.

Therefore, the discriminant is:

b² - 4ac = (-3)² - 4(4)(4) = 9 - 64 = -55

Since the discriminant is negative, this quadratic equation has two complex (non-real) roots.

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The total number of pairs (f, g) ∈ F × F such that g∘f(1) ≠ 1 is 4 * 4 * 4 * 4 = 256.

(a) To find the number of pairs (f, g) ∈ F × F such that g∘f(1) = 1, we need to count the possible functions f and g that satisfy this condition.

Since f is a function from A to A, there are 4 choices for f(1) since f(1) can take any value from A. However, in order for g∘f(1) to be equal to 1, there is only one choice for g(1), which is 1.

For the remaining elements in A, f(2), f(3), and f(4) can each take any value from A, giving us 4 choices for each element. Similarly, g(2), g(3), and g(4) can also take any value from A, giving us 4 choices for each element.

Therefore, the total number of pairs (f, g) ∈ F × F such that g∘f(1) = 1 is 4 * 4 * 4 * 4 = 256.

(b) To find the number of pairs (f, g) ∈ F × F such that g∘f(1) = 1 and g∘f(2) = 2, we need to consider the additional condition of g∘f(2) = 2.

Similar to the previous part, there are 4 choices for f(1) and only one choice for g(1) in order to satisfy g∘f(1) = 1.

For f(2), there is only one choice as well since it must be mapped to 2. This means f(2) = 2.

Now, for the remaining elements f(3) and f(4), each can take any value from A, giving us 4 choices for each element.

Similarly, g(2), g(3), and g(4) can also take any value from A, giving us 4 choices for each element.

Therefore, the total number of pairs (f, g) ∈ F × F such that g∘f(1) = 1 and g∘f(2) = 2 is 1 * 1 * 4 * 4 * 4 * 4 = 256.

Note that the answers for both (a) and (b) are the same since the additional condition of g∘f(2) = 2 does not affect the number of possible pairs.

(c) To find the number of pairs (f, g) ∈ F × F such that g∘f(1) = 1 or g∘f(2) = 2, we need to consider the cases where either g∘f(1) = 1 or g∘f(2) = 2.

For g∘f(1) = 1:

As discussed in part (a), there are 4 choices for f(1) and 1 choice for g(1). For the remaining elements f(2), f(3), and f(4), each can take any value from A, giving us 4 choices for each element. Similarly, g(2), g(3), and g(4) can also take any value from A, giving us 4 choices for each element.

Therefore, the total number of pairs (f, g) ∈ F × F such that g∘f(1) = 1 is 4 * 4 * 4 * 4 = 256.

For g∘f(2) = 2:

As discussed in part (b), there is only one choice for f(2) and one choice for g(2) since f(2) = 2 and g(2) = 2.

For the remaining elements f(1), f(3), and f(4), each can take any value from A, giving us 4 choices for each element. Similarly, g(1), g(3), and g(4) can also take any value from A, giving us 4 choices for each element.

Therefore, the total number of pairs (f, g) ∈ F × F such that g∘f(2) = 2 is 1 * 4 * 4 * 4 * 4 = 256.

Now, to find the total number of pairs (f, g) ∈ F × F such that g∘f(1) = 1 or g∘f(2) = 2, we need to consider the sum of the counts from the two cases. Since these cases are mutually exclusive, we can simply add the counts:

Total number of pairs = 256 + 256 = 512.

Therefore, there are 512 pairs (f, g) ∈ F × F such that g∘f(1) = 1 or g∘f(2) = 2.

(d) To find the number of pairs (f, g) ∈ F × F such that g∘f(1) ≠ 1 or g∘f(2) ≠ 2, we need to consider the cases where neither g∘f(1) = 1 nor g∘f(2) = 2.

For g∘f(1) ≠ 1:

As discussed in part (a), there are 4 choices for f(1) and 1 choice for g(1). For the remaining elements f(2), f(3), and f(4), each can take any value from A, giving us 4 choices for each element. Similarly, g(2), g(3), and g(4) can also take any value from A, giving us 4 choices for each element.

Therefore, the total number of pairs (f, g) ∈ F × F such that g∘f(1) ≠ 1 is 4 * 4 * 4 * 4 = 256.

For g∘f(2) ≠ 2:

As discussed in part (b), there is only one choice for f(2) and one choice for g(2) since

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The average value of f(x, y) = x² + 10y on the rectangle 0 ≤ x ≤ 15, 0 ≤ y ≤ 3 is 112.5.

To find the average value of the function over the given rectangle, we need to calculate the double integral of the function over the rectangle and divide it by the area of the rectangle. The integral we need to evaluate is:

(1/A) ∫(0 to 15) ∫(0 to 3) (x² + 10y) dy dx

where A is the area of the rectangle, which is 15 * 3 = 45.

Evaluating the integral gives:

(1/45) ∫(0 to 15) [x²y + 5y²] from y=0 to y=3 dx

= (1/45) ∫(0 to 15) [3x² + 45] dx

= (1/45) [x³ + 45x] from x=0 to x=15

= (1/45) [33750]

= 750/3

= 250

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In the context of the Mumbai study, the residual is the difference between the observed value (the child's height or arm span) and the predicted value (based on a statistical model or an average value). Therefore, the residual for this child is -3.1 cm.

To calculate the residual, we need to first determine the predicted arm span for a child with a height of 59 cm using the regression equation from the Mumbai study. Let's assume the regression equation is:

Arm span = 0.9*Height + 10

Plugging in the height of 59 cm, we get:

Arm span = 0.9*59 + 10 = 63.1 cm

The predicted arm span for this child is 63.1 cm.

Now, to calculate the residual, we simply subtract the predicted arm span from the actual arm span:

Residual = Actual arm span - Predicted arm span
Residual = 60 - 63.1
Residual = -3.1 cm

Therefore, the residual for this child is -3.1 cm.

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Let’s look at the function f: ZZ. f(z) = 22-32+2.

a) The domain of function f is ZZ (all integers). The codomain of function f is also ZZ. The image (range) of the function f is { -8, -6, 6, 8 }.

b) f(Z+) = { 6, 8 }, f(Z-) = { -8, -6 }.

c) f({2,6}) = { 6 }, f-1({-4}) = {}, f-1({0,-1,-2}) = { 2 } and f¹({2,3,4}) = {}.

Let f(x)=√r+4 and g(x) = 2x − 1.

a) The maximal range for function f such that it is a subset of R is [4, ∞). The maximal range for function g such that it is a subset of R is (-∞, ∞).

b) (fog)(x) = f(g(x)) = √(2x-1+4) = √(2x+3). The maximal range for (fog)(x) such that it is a subset of R is [√3, ∞).

c) (go f)(x) = g(f(x)) = 2√(r+4)-1. The maximal range for (go f)(x) such that it is a subset of R is [1, ∞).

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Answer:

7x+7

Step-by-step explanation:

I'm not really sure which answer you need

7(x+1)

x=-1

The amount quoted by the contractor , given the discount rate and the amounts to be paid, is N 29, 397.19

The amount quoted by the contractor is the total present value of the different future payments by the client.

The present value ( and amount quoted ) is therefore :

= 8, 000 / 1. 10 + 9, 000 / 1. 10 ² + 10, 000 / 1. 10 ³ + 10, 500 / 1. 10 ⁴

= 7, 272.73  + 7, 438.02  + 7, 513.14 + 7, 173.30

= N 29, 397.19

In conclusion, the total quoted was Contractor is $ 29, 397.19 and the amount to be paid every year is N 9, 269.79.

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Answer:

(7x + 9y) (7x - 9y)

Step-by-step explanation:

   49x² - 81y² = 7²*x² - 9²*y²

                      = (7x)² - (9y)²

[tex]\boxed{\text{\bf Use the identity $ a^2 - b^2 = (a + b)(a-b)$} }[/tex]

Here, 'a' corresponds to 7x and 'b' corresponds to 9y.

                      = (7x + 9y) (7x -9y)

According to the concept of probability, there is a 48% chance that a participant who received a placebo will report an improvement.

Of those who received medication A, 56% reported an improvement. This means that the probability of a participant receiving medication A and reporting an improvement is 0.56.

On the other hand, of those who received the placebo, 52% reported no improvement. We can use this information to find the probability of a participant receiving a placebo and reporting an improvement.

To do this, we can use the complement rule of probability, which states that the probability of an event happening is equal to 1 minus the probability of the event not happening. In this case, the event we are interested in is a participant receiving a placebo and reporting an improvement. So, the probability of this event happening is equal to 1 minus the probability of a participant receiving a placebo and not reporting an improvement, which is 0.52.

Therefore, the probability of a participant receiving a placebo and reporting an improvement is:

P(placebo and improvement) = 1 - P(placebo and no improvement)

= 1 - 0.52

= 0.48 or 48%.

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The width of the concrete path is 0.65 m.

The width of the concrete path is calculated as follows;

let the width of the concrete path = x

The dimensions of the shed with the path around it is determined as;

2x + 4  by 2x + 2

The equation for the area of this path becomes;

(2x + 4)(2x + 2)  - (4 x 2) = 9.5

4x² + 4x + 8x + 8 - 8 = 9.5

4x² + 12x = 9.5

4x² + 12x - 9.5 = 0

solve the quadratic equation using formula method;

a = 4, b = 12, and c = -9.5.

The solution becomes, x = 0.65 m or - 3.65

We will take the positive dimension, x = 0.65 m

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The value of area of the star is, A = 1.9 inches

We have to given that;

A ceramic tile has a star-shaped pattern composed of four quarter- circles inside a square with side lengths of 3 inches.

Hence, We get;

Radius of circular cone = 3/2 = 1.5 inches

Now, The value of area of the star is,

A = area of square - area of 4 quarter circle

A = 3 x 3 - 4 (1/4 x 3.14 x 1.5 x 1/5)

A = 9 - 7.065

A = 1.935 inches

A = 1.9 inches

Thus, The value of area of the star is, A = 1.9 inches

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If Abby deposited $3000 and has $3600 at the end of 8 years, then the interest-rate is 2.5%.

The "Simple-Interest" is the interest which is calculated based only on principle amount of a loan or investment, without taking into account any additional interest earned on previous periods.

We can use the simple interest formula to find the annual interest rate:

⇒ Simple Interest = Principle × Rate × Time,

Where: Principle is = initial deposit of $3000,

Rate = annual interest rate (what we need to find)

Time = number of years the money was invested = 8,

The Simple Interest earned over 8 years : $3600 - $3000 = $600,

Substituting the values,

We get,

⇒ $600 = $3000 × Rate × 8,

⇒ Rate = 600/(3000 × 8),

⇒ Rate = 0.025, or 2.5%.

Therefore, the annual interest rate on the account is 2.5%.

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