A survey of North middle school staff included staff members ages the ages were complied and displayed in a histogram which of the following statements best describes the data

By using Mai’s method, the skirt will cost $21.67, By using Elena’s method, the skirt will cost $21 and I think Mai’s method is correct.

(1) We need to find out how much the skirt cost if we use the Mai method. the Mai method is to multiply $30 by 0.80 and then we need to again multiply it with the result which can be given as,

= 30 × 0. 85 × 0. 85

= 21.67

Therefore, By using Mai’s method, the skirt will cost $21.67.

(2) We need to find out how much the skirt cost if we use Elena’s method. Elena’s method is to  multiply $30 by 0. 70 it can be given as,

= 30 × 0. 70

=$21

Therefore, By using Elena’s method, the skirt will cost $21.

(3) I think Mai’s method is correct because she took one 15% discount first and then considered the second discount which is given by the shop. whereas  Elena considered the two discounts at once and calculated it as 30% where the shop offered a 15% discount on the dress and then added a second discount on the purchase cost or bill amount that is why Mai’s method is correct.

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The unit vector in the direction of steepest ascent at P is <-4/sqrt(17), -1/sqrt(17)>,  and the unit vector in the direction of steepest descent at P is <4/sqrt(17), 1/sqrt(17)>.  A vector that points in a direction of no change at P is ⟨-1,1⟩.

To find the direction of steepest ascent/descent at P(-1,1) for f(x,y) = 4x^4 - 4x^2y + y^2 + 9, we need to find the gradient vector evaluated at P and then normalize it to get a unit vector. The gradient vector is given by

grad f(x,y) = <∂f/∂x, ∂f/∂y> = <16x^3 - 8xy, -4x^2 + 2y>

So, at P(-1,1), the gradient vector is

grad f(-1,1) = <16(-1)^3 - 8(-1)(1), -4(-1)^2 + 2(1)> = <-8,-2>

To find the unit vector that gives the direction of steepest ascent, we normalize the gradient vector

||grad f(-1,1)|| = sqrt[(-8)^2 + (-2)^2] = sqrt(68)

So, the unit vector in the direction of steepest ascent at P is

u = (1/sqrt(68))<-8,-2> = <-4/sqrt(17), -1/sqrt(17)>

To find the unit vector that gives the direction of steepest descent, we take the negative of the gradient vector and normalize it

||-grad f(-1,1)|| = ||<8,2>|| = sqrt[8^2 + 2^2] = sqrt(68)

So, the unit vector in the direction of steepest descent at P is

v = (1/sqrt(68))<8,2> = <4/sqrt(17), 1/sqrt(17)>

To find a vector that points in a direction of no change in the function at P, we need to find a vector orthogonal to the gradient vector at P. One such vector is

n = <2,-8>

To see why this works, note that the dot product of the gradient vector and n is

<16x^3 - 8xy, -4x^2 + 2y> . <2,-8> = 32x^3 - 16xy - 4x^2y + 2y^2

Evaluating this at P(-1,1), we get

32(-1)^3 - 16(-1)(1) - 4(-1)^2(1) + 2(1)^2 = 0

So, the vector n is orthogonal to the gradient vector at P and points in a direction of no change in the function.

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The expression 0.85(1.4s) represents the final selling price of the jacket after two price changes: an initial 15% decrease in price, followed by another 15% decrease in price.

The expression 0.85(1.4s) represents the final selling price of the jacket after two price changes. We can break it down into its constituent parts to understand what happened to the price.

Factor 1.4s represents the original selling price of the jacket. This means that the store owner started with a price of 1.4s dollars.

The factor 0.85 represents the first price change. When the store owner lowered the price by 15%, the new price became 0.85 times the original price.

The second factor of 0.85 represents the second price change. After the first price change, the new price was 0.85(1.4s) dollars. When the store owner lowered the price again by 15%, the final selling price became 0.85 times the price after the first price change.

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Options A and D both give an area of 20 square inches

To find the correct dimensions of the parallelogram with an area of 20 square inches, you can use the formula for the area of a parallelogram: Area = base * height.

Given the options:

A. base = 3.06 in, height = 6.54 in
B. base = 6.22 in, height = 3.23 in
C. base = 2.57 in, height = 7.78 in
D. base = 4.00 in, height = 5.00 in

Check each option by plugging the base and height into the formula:

A. 3.06 * 6.54 ≈ 20.00
B. 6.22 * 3.23 ≈ 20.08
C. 2.57 * 7.78 ≈ 19.98
D. 4.00 * 5.00 = 20.00

Options A and D both give an area of 20 square inches. Since the question asks for dimensions to the nearest hundredth of an inch, option A (base = 3.06 in, height = 6.54 in) is more precise and is the correct answer.

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The problem is to find the volume of region E enclosed by a cone and a sphere. The solution involves converting the equations to cylindrical coordinates, finding the limits of integration, and setting up a triple integral. The volume can be calculated by evaluating the integral.

To compute the volume of E using cylindrical coordinates, we first need to find the limits of integration for r, θ, and z. Since E is enclosed by the cone 7 = — x² + y² and the sphere x² + y2 + z2 = 32, we need to find the equations that define the boundaries of E in cylindrical coordinates.

To do this, we convert the equations of the cone and sphere to cylindrical coordinates:

- Cone: 7 = — x² + y² → 7 = — r² sin² θ + r² cos² θ → r² = 7 / sin² θ
- Sphere: x² + y² + z² = 32 → r² + z² = 32

We can see that the cone intersects the sphere when r² = 7 / sin² θ and r² + z² = 32. Solving for z, we get z = ±√(32 - 7/sin² θ - r²). We also know that the cone extends to the origin (r = 0), so our limits of integration for r are 0 to √(7/sin² θ).

For θ, we can see that E is symmetric about the z-axis, so we can integrate over the entire range of θ, which is 0 to 2π.

For z, we need to find the range of z values that are enclosed by the cone and sphere. We can see that the cone intersects the z-axis at z = ±√7. We also know that the sphere intersects the z-axis at z = ±√(32 - r²). Thus, the range of z values that are enclosed by the cone and sphere is from -√(32 - r²) to √(32 - r²) if r < √7, and from -√(32 - 7/sin² θ) to √(32 - 7/sin² θ) if r ≥ √7.

Now that we have our limits of integration, we can set up the triple integral to compute the volume of E:

Vol(E) = ∫∫∫ E dV
= ∫₀^(2π) ∫₀^√(7/sin² θ) ∫₋√(32 - r²)^(√(32 - r²)) F(r, θ, z) dz dr dθ

where F(r, θ, z) = 1 (since we're just computing the volume of E).

Using the limits of integration we found, we can evaluate this triple integral using numerical integration techniques or a computer algebra system.
To find the volume of the region E enclosed by the cone 7 = -x² + y² and the sphere x² + y² + z² = 32, we can use triple integration in cylindrical coordinates. We need to determine the limits of integration for r, θ, and z.

First, rewrite the equations in cylindrical coordinates:
Cone: z = -r² + 7
Sphere: r² + z² = 32

Now, find the intersection between the cone and the sphere by solving for z in the cone equation and substituting it into the sphere equation:
r² + (-r² + 7)² = 32
Solving for r, we get r = √7.

Now, we can find the limits of integration:
r: 0 to √7
θ: 0 to 2π
z: -r² + 7 to √(32 - r²)

Since the volume is the region enclosed by these surfaces, we can set up the triple integral:
Vol(E) = ∫∫∫ r dz dθ dr

With the limits of integration:
Vol(E) = ∫(0 to 2π) ∫(0 to √7) ∫(-r² + 7 to √(32 - r²)) r dz dθ dr

Evaluating this integral will give us the volume of the region E.

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The expression 8(4 - π) yd² is the area of the of the shaded region in terms of π.

The area of the shaded region is the area of the semicircle subtracted from the area of the rectangle

radius of the semicircle is also the width of the rectangle, so;

area of the rectangle = 8 yd × 4 yd = 32 yd²

area of the semicircle = (π × 4 yd × 4 yd)/2

area of the semicircle = 8π yd²

area of the shaded region = 32 yd² - 8π yd²

area of the shaded region = 8(4 - π) yd²

Therefore, the expression 8(4 - π) yd² is the area of the of the shaded region in terms of π.

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Answer:

We know that Miranda ran 4 miles in 28 minutes. Let's set up the proportion:

4 miles / 28 minutes = x miles / 2 minutes

To solve for x, we can cross-multiply:

28 minutes * x miles = 4 miles * 2 minutes

28x = 8

Now, let's solve for x by dividing both sides of the equation by 28:

x = 8 / 28

x = 0.2857

Therefore, Miranda runs approximately 0.2857 miles in 2 minutes.

The value of x which is not a solution to the inequality 5 - 2x ≥ -3, is x = 6.

To find out which value is not a solution to the inequality 5 - 2x ≥ -3, we can substitute each value into the inequality and see if it is true or false.

Let's start with the first value, [tex]x=4[/tex]:

5 - 2(4) ≥ -3
5 - 8 ≥ -3
-3 ≥ -3

Since -3 is greater than or equal to -3, x = 4 is a solution of the inequality.

Now let's try x = 6:

5 - 2(6) ≥ -3
5 - 12 ≥ -3
-7 ≥ -3

Since -7 is less than -3, x = 6 is not a solution of the inequality.

Therefore, the answer is x = 6.

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the roots of the function are[tex]x = 1[/tex] and  [tex]x = 3.[/tex] These are also the x-intercepts of the parabola.

This polynomial is a quadratic function and can be graphed as a parabola. a polynomial of degree two.

[tex]f(x) = x^2 - 4x + 3[/tex]

The coefficient of the x^2 term is positive, which means that the parabola opens upwards. The vertex of the parabola is at (2, -1) and the y-intercept is at (0, 3).

The roots of the function can be found by setting f(x) = 0 and solving for x:

[tex]x^2 - 4x + 3 = 0[/tex]

[tex](x - 3)(x - 1) = 0[/tex]

[tex]x = 1, 3[/tex]

Therefore, the roots of the function are[tex]x = 1[/tex] and  [tex]x = 3.[/tex] These are also the x-intercepts of the parabola.

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The cost of 100 donuts is $ 1 if a dozen of donuts cost 12 cents.

This question is solved using the unitary method. The unitary method is a method in which you find the value of a unit and then the value of the required number of units.

1 dozen refers to a group of 12.

Cost of 1 dozen donuts or 12 donuts = 12 cents

Cost of 1 donut = [tex]\frac{12}{12}[/tex] = 1 cent

Cost of 100 donuts = 1 * 100 = 100 cents

100 cents = 1 dollar.

Thus, the cost of 100 donuts is 100 cents or 1 dollar.

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The percent of change on the item 15%

the percent of change in price of the item can be expressed as:

percent of change = ( | new value - old value | / old value) × 100%

Where the vertical bars indicate absolute value.

Given that; the old price was $80 and the new price is $68. So, we can plug these values into the formula:

percent of change = ( | new value - old value | / old value) × 100%

percent of change = ( | 68 - 80 | / 80) × 100%

percent of change = ( | -12 | / 80) × 100%

percent of change = ( 12 / 80) × 100%

percent of change = ( 0.15 ) × 100%

percent of change = 15%

Therefore, Amazon reduced the price of the item by 15%.

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Answer:

24.1 feet

Step-by-step explanation:

We can represent these 3 points as a triangle:

- place in the water fountain line

- where her lab partner is

- where her friend is

We know that the distance from the water fountain to the lab partner is 6.6 ft, and the distance from the water fountain to the friend is 7.5 ft.

These are the legs (shorter sides) of the right triangle. Now, we need to find the hypotenuse, which is the distance from the lab partner to the friend. We can solve for this using the Pythagorean Theorem.

[tex]a^2 + b^2 = c^2[/tex]

[tex]6.6^2 + 7.5^2 = c^2[/tex]

[tex]43.56 + 56.25 = c^2[/tex]

[tex]99.81 = c^2[/tex]

[tex]c = \sqrt{99.81}[/tex]

[tex]c \approx 10.0 \text{ ft}[/tex]

To finally answer this question, we need to find the perimeter of the triangle (i.e., the distance that will be walked).

[tex]P = 6.6 + 7.5 + 10.0[/tex]

[tex]\boxed{P = 24.1 \text{ ft}}[/tex]

If 75 people chose tulips as their favourite flower then Yelina surveyed 500 people.

What is surveying?

Surveying is a branch of mathematics that deals with the measurement, analysis, and representation of physical features on land or in space. It uses geometry, trigonometry, and infinitesimal calculus to accurately measure distances, angles, elevations, and positions. Surveying is used in various fields such as civil engineering, construction, mapping, and geology to obtain valuable information about the earth's surface and to create maps and plans for various purposes.

According to the given information

Since the central angle for tulips is 54°, we can set up a proportion:

54/360 = 75/x

Simplifying this proportion, we get:

0.15 = 75/x

Multiplying both sides by x, we get:

x * 0.15 = 75

Dividing both sides by 0.15, we get:

x = 500

Therefore, Yelina surveyed 500 people.

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The number of people who liked both milk and curd is 500.

Here's how you can calculate it:

- The number of people who liked only milk is 720.

- The number of people who liked only curd is 880.

- The number of people who did not like either milk or curd is 400.

- Let x be the number of people who liked both milk and curd.

- We can use the formula: Total = Group 1 + Group 2 - Both + Neither.

- Substituting the values, we get: 2500 = 720 + 880 - x + 400.

- Solving for x, we get: x = 500.

- Therefore, 500 people liked both milk and curd.

The number of people who liked at least one of the drinks is 2100.

Here's how you can calculate it:

- The number of people who liked only milk is 720.

- The number of people who liked only curd is 880.

- The number of people who liked both milk and curd is 500.

- Therefore, the total number of people who liked at least one of the drink is: 720 + 880 + 500 = 2100.

Answer:

liked both milks: 900

liked at least 1: 2100

Step-by-step explanation:

there are 2500 people

ONLY LIKE 1 type- 1600 people

400 don't like milk

2500-1600=900

2500-400=2100

The volume of the cone is approximately 133.97 cubic inches. So, correct option is A.

The diameter of the base of a cone is 8 inches, which means that the radius is 4 inches (since radius = diameter/2). The height of the cone is twice the radius, which means the height is 2 x 4 = 8 inches.

The formula for the volume of a cone is V = (1/3)πr²h, where r is the radius and h is the height.

Substituting the values of r and h into the formula, we get:

V = (1/3)π(4²)(8)

V = (1/3)π(16)(8)

V = (1/3)π(128)

V ≈ 133.97 in³

Therefore, correct option is A.

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The required quadratic function is y = -17/324 (x-12)(x-48)

The graph of a function is a visual representation of the relationship between the input values (often referred to as the "domain") and the output values (often referred to as the "range") of the function. The graph is typically drawn on a coordinate plane, with the input values plotted on the horizontal axis and the output values plotted on the vertical axis.

The graph of the function is in the image below:

The domain is (12,48)

Range: (0, 17)

The maximum value is 17

Axis of symmetry: x = 30

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Stewart, Oswaldo, Kevin, and Flynn go to a soccer day at the FC Dallas' arena, Toyota Stadium, in Frisco, Texas. The coach has a computer and video system that can track the height and distance of their kicks. All four soccer players are practicing up-field kicks, away from the goal. Stewart goes first and takes a kick starting 12 yards out from the goal. His kick reaches a maximum height of 17 yards and lands 48 yards from the goal. Oswaldo goes next and the computer gives the equation of the path of his kick as y=-= +148 - 24, where y is the height of the ball in yards and x is the horizontal distance of the ball from the goal line in yards. After Kevin takes his kick, the coach gives him a printout of the path of the ball Hegy Kevin's Kick Finally, Flynn takes his kick but the computer has a problem and can only give him a partial table of data points of the ball's trajectory. Flynn's Table: Distance from the 10 11 12 13 14 15 16 17 18 19 20 goal line in yards Height in yards 0 4.7 8.75 12.2 15 17.2 18.75 19.7 20 19.7 18.75 The computer is still not working but Stewart, Oswaldo, Kevin, and Flynn want to know who made the best kick. For each soccer player, • Write an equation to represent the quadratic function. • Create a graph to represent the quadratic functions • Identify the following: Domain o Range Maximum value (height) Axis of Symmetry x-intercepts Which soccer player made the best kick? Whose kick went the highest? Whose kick went the longest? Explain your answer and support with reasoning.

The value of x is -4.

We have,

(3x + 25) and (6x - 2) makes one angle.

So,

(9x + 23) is the angle.

Now,

It is bisected in two angles.

So,

9x + 23 = 1/2 x (6x - 2)

9x + 23 = 3x - 1

9x - 3x = -1 - 23

6x = -24

x = -4

Thus,

The value of x is -4.

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Since we have shown that all four angles formed by the lateral sides are right angles, and the opposite sides are parallel and congruent, we can conclude that the lateral sides are rectangles.

Yes, we can prove that the lateral sides are rectangles based on the given information.

Firstly, we can see that the two diagonals of the lateral sides are congruent (both measure 13 cm), which means that the opposite sides of the figure are parallel. This is because, in a rectangle, opposite sides are parallel and congruent.

Next, we can use the converse of the Pythagorean theorem to determine if the angles are right angles. The converse of the Pythagorean theorem states that if the square of the length of the longest side of a triangle is equal to the sum of the squares of the other two sides, then the triangle is a right triangle.

For each of the lateral sides of the figure, we can consider the two triangles formed by one of the diagonals and the adjacent sides. Applying the Pythagorean theorem, we can see that:

For the first lateral side, we have:

(5 cm)^2 + (12 cm)^2 = (13 cm)^2

Therefore, the angles between the 5 cm and 12 cm sides are right angles.

For the second lateral side, we have:

(5 cm)^2 + (12 cm)^2 = (13 cm)^2

Therefore, the angles between the 5 cm and 12 cm sides are also right angles.

Since we have shown that all four angles formed by the lateral sides are right angles, and the opposite sides are parallel and congruent, we can conclude that the lateral sides are rectangles.

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R = 1/8 and the interval of convergence is (-1/8, 1/8).

We can use the ratio test to determine the radius of convergence:

lim_n→∞ |(ε_n+1 - 3)(8x - 3)^n+1 / (ε_n - 3)(8x - 3)^n)|

= lim_n→∞ |(ε_n+1 - 3)/(ε_n - 3)| |8x - 3|

Since the limit of the ratios of consecutive terms is independent of x, we can evaluate it at any particular value of x, such as x = 0:

lim_n→∞ |(ε_n+1 - 3)/(ε_n - 3)| = 1/8

Therefore, the series converges absolutely for |8x - 3| < 1/8, and diverges for |8x - 3| > 1/8. We also need to check the endpoints of the interval:

When 8x - 3 = 1/8, the series becomes Σε_n, which diverges since ε_n is not a null sequence.

When 8x - 3 = -1/8, the series becomes Σ(-1)^nε_n, which converges by the alternating series test, since ε_n is decreasing and approaches zero.

Thus, the interval of convergence is (-1/8, 1/8).

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When both the increasing acreage and the increasing yield are considered, the total number of bushels of corn currently increasing at a rate of 4000 bushels per year.

The wheat farmer is currently farming 400 acres of corn and increasing that number by 20 acres per year. He harvests 120 bushels of corn per acre, with an increasing yield of 4 bushels per acre per year.

To determine the rate of increase in the total number of bushels, we need to consider both the increasing acreage and the increasing yield.

First, let's find the increase in bushels due to the increasing acreage:
20 acres/year * 120 bushels/acre = 2400 bushels/year

Next, let's find the increase in bushels due to the increasing yield:
400 acres * 4 bushels/acre/year = 1600 bushels/year

Now, add both increases together to find the total increase in bushels:
2400 bushels/year + 1600 bushels/year = 4000 bushels/year

So, the total number of bushels of corn is currently increasing at a rate of 4000 bushels per year.

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The height of the cone is 3.4cm

A cone is a shape formed by using a set of line segments or the lines which connects a common point, called the apex or vertex.

The volume of a cone is expressed as;

V = 1/3 πr²h

where πr² = base area. therefore the volume can be written as;

V = 1/3 base area × height

base area = 49cm²

height = 45.3 cm³

45 = 1/3 ×40h

135 = 40h

h = 135/40

h = 3.4cm

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The probability of Jeremy selecting a jelly bean that is not lemon or orange is: 26/48 = 0.54 or 54%.

To find the probability that Jeremy randomly selects a jelly bean that is not lemon or orange, we need to first find the total number of jelly beans that are not lemon or orange.

The number of grape jelly beans is 10, the number of cherry jelly beans is 16, so the total number of jelly beans that are not lemon or orange is:

10 + 16 = 26

The total number of jelly beans in the dish is:

10 + 8 + 14 + 16 = 48

Therefore, the probability of Jeremy selecting a jelly bean that is not lemon or orange is:

26/48 = 0.54 or 54%.

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The distance between the points P(-4, 2, 1) and Q(-1, 2, 0) is [tex]\sqrt{(10)}[/tex] units.

The distance formula is derived from the Pythagorean theorem, which states that in a right triangle, the sum of the squares of the lengths of the legs (the sides that form the right angle) is equal to the square of the length of the hypotenuse (the side opposite the right angle).

In three-dimensional space, we have to use a variation of the Pythagorean theorem that involves finding the distance between the two points in each of the three dimensions (x, y, and z) and then adding up the squares of those distances, before taking the square root of the sum.

To find the distance between two points P(x1, y1, z1) and Q(x2, y2, z2) in three-dimensional space, we use the distance formula:

d = [tex]\sqrt{((x_2 - x_1)^2 + (y_2 - y_1)^2 + (z_2 - z_1)^2)}[/tex]

Using the given points P(-4, 2, 1) and Q(-1, 2, 0), we have:

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

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

= [tex]\sqrt{(10)}[/tex]

Therefore, the distance between the points P(-4, 2, 1) and Q(-1, 2, 0) is sqrt(10) units.

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Let's assume that the hourly rate for loading and unloading is $x and the hourly rate for packing and unpacking is $y.

From the given information, we can form the following two equations:

[tex]8x + 6y = 890[/tex] ...(1) (for 8 hours of loading and unloading and 6 hours of packing and unpacking)

[tex]5x + 3y = 515[/tex] ...(2) (for 5 hours of loading and unloading and 3 hours of packing and unpacking)

To solve for x and y, we can use the method of elimination.

Multiplying equation (2) by 2, we get:

[tex]10x + 6y = 1030[/tex] ...(3)

Now, subtracting equation (1) from equation (3), we get:

2x = 140

Therefore, x = $70 per hour.

Substituting the value of x in equation (2), we get:

5(70) + 3y = 515

Simplifying, we get:

3y = 165

Therefore, y = $55 per hour.

Hence, the company's hourly rates are $70 per hour for loading and unloading and $55 per hour for packing and unpacking.

In summary, we can set up a system of equations to solve for the hourly rates of a moving team.

From there, using the method of elimination, we can solve for the hourly rates for both loading and unloading as well as packing and unpacking.

In this case, the hourly rate for loading and unloading is $70 per hour, and the hourly rate for packing and unpacking is $55 per hour.

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The z scοre is negative the actual probability would be

1-0.7995 = 0.2005

What is the probability?

A number that expresses hοw likely it is that an event will occur is called the probability of οccurrence. It is written as a number from 0 to 1, or frοm 0% to 100%, in percentage notation. The probability of an event occurring increases with probability.

here,

mean = 20.20

standard deviatiοn = 2.60

we knοw that,

Z scοre = (X-mean)/standard deviation

fοr X = 18:

Z scοre = (18-20.20)/2.6 = -0.8461

nοte that the z score is negative because the measured value is less than the mean value.

fοr Z score 0.8461 probability is 0.7995

and since the z scοre is negative the actual probability would be

1-0.7995 = 0.2005

a. For nοt within 1 hour of the population mean

We apply the formula here and we get the value οf P.

P(19.20>x>21.20) = P(19.20-20.20/2.60√18) > X-μ/σ√n >21.20-20.20/2.60√18

P(19.20>x>21.20) = P(-1.63>z>1.63)

Now, we find the value οf z.

P(19.20>x>21.20) = P(z>1.63) + P(z<-1.63)

P(19.20>x>21.20) = 0.0516 + 0.0516

P(19.20>x>21.20) = 0.1032

b. Fοr 20. 0 to 20. 5 hours

P(20<x<20.5) = P(20-20.20/2.60√18) < X-μ/σ√n<20.50-20.20/2.60√18

P(20<x<20.5) = P(-0.33<z<0.49)

Nοw, we find the value of the z-score and we get

P(20<x<20.5) = P(z<0.49) - P(z<-0.33)

P(20<x<20.5)  = 0.6879 - 0.2707

P(20<x<20.5)  = 0.3172

c. Fοr at least 22 hours

We apply the t-test fοrmula here and we get

P(x≥22) = P(X-μ/σ√n≥22-20.20/2.60√18)

Nοw, we find the value of z.

P(x≥22) = P(z≥2.94)

P(x≥22) = 0.0016

d. Fοr not more than 21 hours.

P(x<21) = P(X-μ/σ√n<21-20.20/2.60√18)

We find here the value οf P for x<21 and we get

P(x<21) = P(z<1.31)

Now, we find the value οf the z- score.

P(x<21) = 0.9049

Hence, a. 0.1032

b.  0.3172

c. 0.0016

d. 0.9049

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Complete question is,

Among college students who hold part-time jobs during the school year, the distribution of the time spent working per week is approximately normally distributed with a mean of 20.20 hours and a standard deviation of 2.60 hours. Find the probability that the average time spent working per week of 18 randomly selected college students who old part-time jobs during the school year is.

To factor the polynomial x^2 - x - 6, we need to find two binomials whose product is equal to this polynomial. We can use the following methods to factor the polynomial:

Method 1: Factoring by inspection

- We know that x^2 is the product of x and x, so we can start with the binomial (x )(x ) as a factorization of x^2.

- We then look for two numbers whose product is -6 and whose sum is -1.

- The two numbers are -3 and 2, since (-3)(2) = -6 and (-3) + 2 = -1.

- Therefore, the polynomial x^2 - x - 6 can be factored as (x - 3)(x + 2).

Method 2: Using the quadratic formula

- We can also use the quadratic formula to find the roots of the polynomial, which are the values of x that make the polynomial equal to zero.

- The quadratic formula is x = (-b ± sqrt(b^2 - 4ac)) / 2a, where a = 1, b = -1, and c = -6.

- Plugging in these values, we get x = (-(-1) ± sqrt((-1)^2 - 4(1)(-6))) / 2(1) = (1 ± sqrt(25)) / 2.

- Simplifying, we get x = 3 or x = -2.

- Therefore, the polynomial x^2 - x - 6 can be factored as (x - 3)(x + 2).

So, the pairs of polynomials that, when multiplied together, result in the polynomial x^2 - x - 6 are (x - 3) and (x + 2), as well as (x + 2) and (x - 3).

a) The number of cities that had only a professional sports team can be found by subtracting the number of cities that had a professional sports team and a symphony, the number of cities that had a professional sports team and a children's museum, and the number of cities that had all three activities from the total number of cities:

33 - (9 + 6 + 3) = 15 cities had only a professional sports team.

b) The number of cities that had a professional sports team and a symphony, but not a children's museum can be found by subtracting the number of cities that had all three activities from the number of cities that had a professional sports team and a symphony:

9 - 3 = 6 cities had a professional sports team and a symphony, but not a children's museum.

c) The number of cities that had a professional sports team or a symphony can be found by adding the number of cities that had a professional sports team, the number of cities that had a symphony, and then subtracting the number of cities that had both:

17 + 15 - 9 + 14 - 6 + 3 = 34 cities had a professional sports team or a symphony.

d) The number of cities that had a professional sports team or a symphony, but not a children's museum can be found by subtracting the number of cities that had all three activities from the answer to part c:

34 - 3 = 31 cities had a professional sports team or a symphony, but not a children's museum.

e) The number of cities that had exactly two of the activities can be found by adding up the number of cities that had a professional sports team and a symphony, the number of cities that had a professional sports team and a children's museum, and the number of cities that had a symphony and a children's museum, and then subtracting twice the number of cities that had all three activities:

9 + 6 + 6 - 2(3) = 15 cities had exactly two of the activities.

(a) With 98% confidence, the true average student loan debt for university students in Canada falls between $25,883.5 and $26,116.5.

(b) No, this does not contradict the reported average of $26,500.

(a) To construct a 98% confidence interval, we can use the formula:

CI = [tex]\bar{x}[/tex] ± z* (σ/√n)

where [tex]\bar{x}[/tex] is the sample mean, σ is the population standard deviation (unknown), n is the sample size, and z* is the z-value from the standard normal distribution that corresponds to the desired level of confidence (98% in this case).

Substituting the given values, we get:

CI = 26,000 ± 2.33 * (500/√64)
CI = 26,000 ± 116.5
CI = (25,883.5, 26,116.5)

Therefore, we can say with 98% confidence that the true average student loan debt for university students in Canada falls between $25,883.5 and $26,116.5.

(b) No, this does not contradict the reported average of $26,500. The reported average is within the confidence interval we calculated, which means that it is a plausible value for the true average. The sample mean of $26,000 is slightly lower than the reported average, but this could be due to random sampling error.

Overall, we cannot make a definitive conclusion about the true average based on this sample alone, but we can say with 98% confidence that it falls within the range of $25,883.5 to $26,116.5.

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the actual perimeter of the living room  in the scale drawing  is 216 inches.

We can precisely portray locations, areas, structures, and details in scale drawings at a scale that is either smaller or more feasible than the original.

When a drawing is said to be "to scale," it signifies that each piece is proportionate to the real or hypothetical entity; it may be smaller or larger by a specific amount.

When something is described as being "drawn to scale," we assume that it has been printed or drawn to a conventional scale that is accepted as the norm in the construction sector.

When our awareness of scale improves, we are better able to quickly recognize the spaces, zones, and proposed or existent spatial relationships when looking at a drawing at a given scale.

One metre is equivalent to one metre in the actual world. When an object is depicted at a 1:10 scale, it is 10 times smaller than it would be in real life.

You might also remark that 10 units in real life are equivalent to 1 unit in the illustration.

If the length and breadth of the living room in real life are 9/4 inches each, we can use the given scale of the drawing to find the corresponding dimensions of the living room in the drawing:

1/4 inch = 2 feet

So, 9/4 inches in real life is equal to:

(9/4) inches / (1/4 inch per 2 feet) = 18 feet

This means that each side of the living room in the drawing would be 18/2 = 9 inches long.

To find the actual perimeter of the living room, we need to convert the dimensions back to real-life measurements and add up the lengths of all four sides:

Length in real life = 9/4 inches x 2 x 12 inches/foot = 54 inches

Breadth in real life = 9/4 inches x 2 x 12 inches/foot = 54 inches

Perimeter in real life = 2 x (Length + Breadth)

Perimeter in real life = 2 x (54 inches + 54 inches)

Perimeter in real life = 2 x 108 inches

Perimeter in real life = 216 inches

Therefore, the actual perimeter of the living room is 216 inches.

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