I keep messing up somebody please help me

Answer:

40 hours

Step-by-step explanation:

This is an example of a work-rate-time problem

Since the experienced roofer can finish the job in 24 hours, his rate of work would be 1/24 (of the roof) per hour

Let the time taken by the trainee alone be x hours

His rate of work = [tex]\dfrac{1}{x}[/tex]

Together they finish the roof in 15 hours
So combined work rate = [tex]\dfrac{1}{15}[/tex]

Since combined rate = sum of individual rates we get

[tex]\dfrac{1}{24} +\dfrac{1}{x} = \dfrac{1}{15}[/tex]

Move 1/24 to the right side:
[tex]\dfrac{1}{x} = \dfrac{1}{15} - \dfrac{1}{24}[/tex]

[tex]\dfrac{1}{x} =\dfrac{24 - 15}{24\cdot 15} = \dfrac{9}{360}\\\\[/tex]

Taking reciprocals on both sides

[tex]x = \dfrac{360}{9} = 40 \;hours[/tex]

Answer:

y = 5x

Step-by-step explanation:

It can be observed that as ‘x’ increases, ‘y’ also increases.

It can also be observed that

[tex]\frac{y}{x}[/tex] = the same constant for all four sets of values

k =[tex]\frac{10}{2} = \frac{20}{4} = \frac{30}{6} =\frac{40}{8}[/tex]=5

It can concluded that y is directly proportional to x:

y = kx                      Where k = constant of proportionality

For these four sets of values:

y = 5x

Approximately 99.7% of the vehicles travel between 53 miles per hour and 77 miles per hour.

The Empirical Rule states that, for a normally distributed random variable, the symmetric distribution of scores is presented as follows:

The mean and the standard deviation for this problem are given as follows:

Hence:

Meaning that the approximate percentage is of 99.7%.

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The function as the same as y = 3 cosine (2 (x + Start Fraction pi Over 2 End Fraction)) minus is y = -3 sin(2(x + π/4)) - 2 Option B

Sine and cosine have the following relationship:

cos(θ) = sin (π/2 - θ)

y = 3 cos(2 (x + π/2)) - 2

y = 3 cos(2x + π) - 2

Let θ = 2x + π,

therefore using Sine and cosine have the following relationship:

cos(2x + π) = sin (π/2- (2x + π))

= sin (π/2 - 2x - π)

= sin (-2x - π/2)

= sin (-2(x + π/4))

but sin(-θ) = -sin (θ)

Therefore:

sin (-2(x + π/4)) = -sin (2(x + π/4))

= - sin (2(x + π/4)) = cos(2x + π)

y = 3 cos(2x + π) - 2 = 3[ - sin (2(x + π/4))] -2

y = -3 sin (2(x + π/4)) -2

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The functions and equations y = f(x) = 7·x³, x = 5, Δx = 0.06, indicates that we get;

a) Δy = 31.879512

b) dy = 21·x²dx

c) dy = 31.5

A function is a rule that maps input variables to output variables in a relationship in which an input is assigned to exactly one output.

a) The value of the function y = f(x) = 7·x³

The value of x = 5

Value of the change in x, Δx = 0.06

The change in y, Δy is therefore;

Δy = f(x + Δx) - f(x), from which we get;

Δy = f(5 + 0.06) - f(5) = f(5.06) - f(5)

Δy = f(5.06) - f(5)

Plugging in the values of x = 5.06, and x = 5 in the function f(x), we get;

f(5.06) = 7 × (5.06)³ = 906.879512

f(5) = 7 × 5³ = 875

Therefore; Δy = f(5.06) - f(5) = 906.879512 - 875 = 31.879512

Δy = 31.879512

b) dy = f'(x)dx

f'(x) is the derivative of the function f(x)

dy/dx = f'(x)  = 3 × 7 × x² = 21·x²

dy/dx = f'(x) = 21·x²

dy = f'(x)dx = 21·x²dx

dy = 21·x²dx

c) dy for the given x and Δx values can be found by plugging in x = 5 and dx = Δx = 0.06 in the equation, dy = 21·x²dx, as follows;

dy = 21 × 5²× 0.06 = 31.5

dy = 31.5

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The linear expression for 2h - 1 and 3h + 4 is 5h + 3. The solution has been obtained by using the arithmetic operations.

What are arithmetic operations?

According to mathematicians, the four fundamental operations, also referred to as "arithmetic operations," can be used to describe all real numbers. Division, multiplication, addition, and subtraction are the four mathematical operations that result in the terms quotient, product, sum, and difference, respectively.

We are given two expressions as 2h - 1 and 3h + 4.

On adding both, we get

2h - 1 + 3h + 4 = 5h + 3

Hence, the linear expression for 2h - 1 and 3h + 4 is 5h + 3.

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Answer: The height of the stone after time "t" is given by the function h(t) = 100t - 5t^2, where t is in seconds. To find the maximum height, we need to find the value of t for which the height is greatest.

To do this, we can take the derivative of h(t) with respect to t, which gives us the rate of change of height with respect to time. Then, we can set this derivative equal to 0 and solve for t. The value of t that satisfies this condition will be the time at which the height is at its maximum.

h'(t) = 100 - 10t

Setting h'(t) = 0, we get:

100 - 10t = 0

10t = 100

t = 10

So, the maximum height is h(10) = 100 * 10 - 5 * 10^2 = 100 - 500 = -400 meters.

Since the height cannot be negative, the maximum height the stone can reach is 100 meters.

Step-by-step explanation:

Check the picture below.

There must be two that meet on the same day, assuming that no classes are held on weekends.

Sets are groups of clearly defined objects or elements in mathematics. A set is denoted by a capital letter, and the cardinal number of a set is enclosed in a curly bracket to indicate how many members there are in a finite set.

Let us show that in any set of six classes, each meeting regularly once a week on a particular day of the week, there must be two that meet on the same day, assuming that no classes are held on weekends.

Since there are 5 working days by a week and 6 classes, by Pigeonhole Principle there must be two that meet on the same day.

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Step-by-step explanation:

Choice A.

Choice A is exponentially because the amount is double each day. In other words each day the amount gets larger. One day it increased by 10 cents, the next day 20 cents, the next day 40 cents and so on... eventually it'll be a day where it increases by a million cents.

Choice B is not exponentially, it is linearly because each day the amount increase stays the same. One day is $5.00 more, the next day it's $5.00 more, the next day it's $5.00 more... and so on.

Because of that, we can get rid of those two choice B options.

Both Choice A's look the same. The only difference is that one has a 2 and the other doesn't. That 2 indicates that we're doubling. Makes sense because that's what we associate with doubling.

Making the second Choice A the correct formula.

The solution is, each tour guide have an equal number of 8 students.

In mathematics, multiplication is a method of finding the product of two or more numbers. It is one of the basic arithmetic operations, that we use in everyday life.

here, we have,

there are 12 students in each class.

Four classes are on a field trip.

There are 6 tour guides.

total students = 12*4

                       = 48

so, each guide have = 48/6

                                  = 8

Hence, The solution is, each tour guide have an equal number of 8 students.

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A unit can be used for measurement, and is commonly found in mathematics to describe length, size, etc.

First, because we are dealing with different units here, we need to know how many milliliters are in a litre.

So, an equation we can use is:

If we look at 1.2 litres, we can now convert it to milliliters.

Comparing 1200ml to 140ml, we can see that 1200ml is bigger.

Therefore, 1.2 litres are greater.

The greatest volume and smallest volume container is of rice and flour.

Suppose that the radius of considered right circular cylinder be 'r' units.

And let its height be 'h' units.

Then, its volume is given as:

[tex]V = \pi r^2 h \: \rm unit^3[/tex]

Right circular cylinder is the cylinder in which the line joining center of top circle of the cylinder to the center of the base circle of the cylinder is perpendicular to the surface of its base, and to the top.

Given;

Sugar container radius and height is 2.5in and 8.5inch

Rice container radius and volume is 2.5in and 235.3inch^3

Sugar container area of base and height is 12.26in and 4inch

Now,

1. volume= pi*r*r*h

=3.14*2.5*2.5*8.5

=166.8125

2. volume= pi*r*r*h

235.3=3.14*2.5*2.5*h

h=11.98in

3. volume= base*h

=12.26*4

=49.04in^3

Therefore, the volume of flour container is 49.04in^3.

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A is directed along negative X and Y axes respectively having magnitudes 3.214 and 3.83 units respectively.

A vector is an object that, as we all know, possesses both magnitude and direction. We must determine a vector's length in order to determine its magnitude. Vector quantities include things like velocity, displacement, force, momentum, etc. However, scalar quantities like as speed, mass, distance, volume, temperature, etc. exist. In contrast to vectors, which

have both magnitude and direction, scalars only have magnitude.

Magnitude of vector A = |A| = 5 units

We know, the negative Y-axis is an angle of 270° counterclockwise with a positive X-axis.

θ = Angle of vector A with positive X-axis = (270° - 40°) = 230°

So, x component of vector A = Ax = |A| * cos 230° = |A| * cos (180° + 50°) = |A| * (- cos 50°) = 5 * (-0.6428) = -3.214

And, y component of vector A = Ay = |A| * sin 230° = |A| * sin (180° + 50°) = |A| * (- sin 50°) = 5 * (-0.766) = -3.83

Since Ax and Ay both are negative relative to positive X and Y axes respectively; so, the x and y components of vector A are directed along negative X and Y axes respectively having magnitudes 3.214 and 3.83 units respectively.

the complete question is -

Vector img has a magnitude 5.00 and points in a direction 40.0° clockwise from the negative y axis.What are the x and y components of vector img .

A)Ax = 3.83 and Ay = 3.21

B)Ax = 3.83 and Ay = -3.21

C)Ax = -3.21 and Ay = -3.83

D)Ax = -3.21 and Ay = 3.83

E)Ax = 4.29 and Ay = 2.16

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The value of x that makes MBUL a kite is given as follows:

x = 6.

For MBUL to represent a kite, the following lengths have to be congruent:

BA and AL.

The lengths for this problem are defined as follows:

As the sides are congruent, the equation is given as follows:

BA = LA.

Hence the value of x that makes MBUL a kite is obtained as follows:

3x - 1 = 17

3x = 18

x = 18/3

x = 6.

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The x-intercept is -3 and the vertex of the parabola is (-1.5, -13.5).

The intersection of two lines, two line segments, or any other suitable arrangement of rays, segments, and lines that results in two straight "sides" coming together at one location is known as an angle's vertex.

The x coordinate of the vertex is given as:

x = -b/2a= -18/ 2(6)= - 1.5

The y coordinate of the vertex is given as:

y = f(- 1.5)

f(- 1.5) = 6(- 1.5)² + 18(- 1.5) = 13.5 - 27= -13.5

Hence, the vertex of the parabola is (-1.5, -13.5).

The x intercept is found by substituting the value of y = 0 in the function:

0 = 6x² + 18x

0 = 6x (x + 3)

x + 3 = 0

x = -3

Hence, the x-intercept is -3 and the vertex of the parabola is (-1.5, -13.5).

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The conversion factor of litre to quarts is 1 litre = 1.057 quarts and its meaning is discussed below.

What is a conversion factor?

A conversion factor is a number that is used to multiply or divide one set of units into another. If a conversion is required, it must be done using the correct conversion factor to get an identical value. The correct conversion factor to convert minutes to hours is 60 minutes = 1 hour.

The metric unit of a volume known as the litre is mostly used to measure liquids.

An English measurement of volume equal to the one-quarter gallon is the quart. There are now three different types of quarts in use: the liquid quart, dry quart, and imperial quart of the British imperial system.

The standard value of converting liquid to quarts is 1 litre = 1.057 quarts.

This means that volume of 1 litre of a substance is equivalent to the volume of 1.057 quarts of the same substance.

Therefore the conversion factor of litre to quarts is 1 litre = 1.057 quarts.

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The nontrivial solution to the equation Ax = 0 is x = [1, 1, 1]^T.

What is the nontrivial solution?

To find a nontrivial solution to the equation Ax = 0, where A is the given matrix, we need to find a vector x that satisfies the equation and is not the trivial solution x = 0.

We can start by using the observation that the first column plus twice the second column equal the third column:

4x1 - 7x2 + 9x3 = 0

x1 + 2x2 - 3x3 = 0

6x1 + 3x2 + 3x3 = 0

Applying row reduction to the matrix A, we find:

{{4,1,6},{-7,5,3},{9,-3,3}}

{{1,1/2,-3/2},{-7,5,3},{9,-3,3}}

{{1,1/2,-3/2},{0,11/2,15/2},{0,11/2,15/2}}

The rank of the matrix A is 2, which is less than the rank of the matrix of the system of linear equations, which is 3. This means there is a nontrivial solution to the equation Ax = 0.

One such nontrivial solution can be found by setting x3 = 1 and solving for x1 and x2:

x1 + 2x2 - 3(1) = 0

x1 + 2x2 = 3

x1 = 3 - 2x2

Setting x2 = 1, we find:

x1 = 3 - 2(1) = 1

x2 = 1

x3 = 1

Hence, a nontrivial solution to the equation Ax = 0 is x = [1, 1, 1]^T.

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Answer:

16.00

Step-by-step explanation:

400 divided by 25 is also 16, so divide that and it should be the same as 40 divided by 2.5

QUOTIENT-

The answer to a division problem

40/2.5 =

16

Olivia could have used a translation and a rotation to move ABCDE onto A'B'C'DE".

Distance in numerical measurement of how far apart to 16 places in point are in space age is often measured in unit like came miles with as for free system also can be conceptualized in the term of time as Indian distance between two points in the time.

A translation would involve shifting the figure ABCDE along some axis by a certain distance, while a rotation would involve rotating the figure ABCDE around a fixed point. By combining the two transformations, Olivia could move ABCDE onto A'B'C'DE".

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Therefore , the solution of the given problem of percentage comes out to be  19.9%  is the percent change.

In mathematics, a percentage is any value that can be written as a proportion of 100. There are also sporadic uses of the abbreviations "pct.," "pct," or "pc." However, it is commonly indicated by the "%" mark. The proportional amount is flat and lacks any dimensions. Since percentages have a numerator of 100, they can be thought of as fractions. The cent symbol (%) must come after a number to denote that it is a percentage.

Here,

Given:

You can compute 1.99 as a percent of a given number x by dividing 1.99 by x and multiplying the outcome by 100.

For instance,

if 1.99 is expressed as a percentage of 10,

then

=> 1.99 x 100% = 19.9%

Therefore , the solution of the given problem of percentage comes out to be  19.9%  is the percent change.

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Answer: To calculate the simple interest, you can use the formula:

I = Prt

where I is the interest, P is the principal (the amount borrowed), r is the interest rate as a decimal, and t is the time in years.

In this case, P = $4,200, r = 0.03, and t = 6/12 = 0.5 (since the interest is paid over 6 months, which is half of a year). Plugging these values into the formula, we get:

I = Prt = 4,200 * 0.03 * 0.5 = $63

So, Jimena will pay the store $63 in simple interest.

Step-by-step explanation:

Answer:    (x,y)=(3,-1)

Step-by-step explanation:

The answer to question of trail mix in ascending order would be, 1/2 cup cereal, 3/4 cup raisins, 1/3 cup almonds, 2/3 cup peanuts.

The order of ingredients from least to greatest for Juan's trail mix recipe is: 1/2 cup cereal, 3/4 cup raisins, 1/3 cup almonds, and 2/3 cup peanuts. Juan's mother provided the recipe which consists of a combination of dried fruits, nuts, and cereal. The recipe calls for 1/2 cup of cereal, which is the least amount of any of the ingredients. The next ingredient is 3/4 cup of raisins, followed by 1/3 cup of almonds, and finally 2/3 cup of peanuts, which is the greatest amount of any of the ingredients. These ingredients can be combined and enjoyed as a snack.

Hence the answer is, 1/2 cup cereal, 3/4 cup raisins, 1/3 cup almonds, 2/3 cup peanuts.

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Answer:

Step-by-step explanation:

Given triangle WXY with sides WX = 7 in and XY = 7 in and angle X = 60°, you want the measure of angle Y and the length of side WY.

The equal given side measures tell you that their opposite angles (W and Y) have equal values. Those values will be such that the total of all angles is 180°:

  W +Y +X = 180°

  Y +Y +60° = 180° . . . . . . . . . . . use given values; substitute Y for W

  Y = (180° -60°)/2 = 60° . . . . . . . subtract 60°, divide by 2

All of the angles in this triangle have the same measure, so it is an equilateral triangle. All of the sides have the same measure, too.

  angle Y = 60°

  WY = 7 inches

__

Additional comment

It is helpful to recognize that an isosceles triangle with a vertex angle of 60° is an equilateral triangle. That recognition lets you write down the answer with no further work.

The coin flip is random variable.

What is probability?

Simply put, probability measures how probable something is to occur. We can discuss the probabilities of various outcomes, or how likely they are, whenever we are unsure of how an event will turn out. Statistics is the study of events subject to probability.

The likelihood that a population parameter will be less than a given value when the null hypothesis is true is expressed as the p-value, also known as a probability value or a measure of significance, for a particular statistical model.

A variable at random The value of the variable X is subject to chance. Imagine that you flip a coin. If the coin lands on its head, you win one dollar; otherwise, you lose one. You can never predict how much money you'll make from one coin toss.

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The coin flip is random variable.

What is probability?

Simply put, probability measures how probable something is to occur. We can discuss the probabilities of various outcomes, or how likely they are, whenever we are unsure of how an event will turn out. Statistics is the study of events subject to probability.

The likelihood that a population parameter will be less than a given value when the null hypothesis is true is expressed as the p-value, also known as a probability value or a measure of significance, for a particular statistical model.

A variable at random The value of the variable X is subject to chance. Imagine that you flip a coin. If the coin lands on its head, you win one dollar; otherwise, you lose one. You can never predict how much money you'll make from one coin toss.

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Answer:

Step-by-step explanation:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Triangles PQR and ZQX are similar!

Square side => a

XZ / (PQ - PZ) = PR / PQ

a / (12 - a) = 8 / 12

a = 4.8

The side length of the square PZXY is sqrt(2).

A square is a two-dimensional figure that has four sides and all four sides are equal.

The area of a square is given as side².

We have,

Since triangle PQR is a right triangle, we can use the Pythagorean theorem to find the length of QR:

QR² = PQ² + PR²

QR² = 1² + 1²

QR² = 2

QR = √2

Since PZXY is a square, its sides are equal in length.

Let's denote the length of one side of the square as s.

Then, we can write:

PR = PX + RX

1 = s + QY

Since QY = PZ = s and PX = QX = QR - QY = sqrt(2) - s,

we can substitute these values into the equation for PR to get:

1 = s + (√2 - s)

1 = √2

Therefore,

The side length of the square PZXY is √2.

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The sample space of the tossed coin: head or Tail =[ HT ]

The sample space of the die : [1, 2, 3, 4, 5,6 ]

The sample space of the ball {0 , 1, 2, 3, 4, 5, 6, 7, 8, 9]

experiment 1: In a large number of repetitions of the experiment, the relative frequency of each outcome (Heads or Tails) would be approximately 0.5 or 50%.

Experiment 2: In a large number of repetitions of the experiment, the relative frequency of each outcome (1 to 6) would be approximately 0.1667 or 16.67%.

Experiment 3: In a large number of repetitions of the experiment, the relative frequency of each outcome (0 to 9) would be approximately 0.1 or 10%.

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The row in the original matrix and the column in the primary matrix must match. Hence, the matrix product has the first matrix's number of rows and the second matrix's number of columns.

Read an overview of this subject. a collection of numbers lined up in rows or columns to form a flat array is called a matrix. The atoms, or units, of the matrix are the integers.

The study of squares is the main focus of the mathematical field known as matrix theory. It started out as a branch of linear algebra but quickly expanded to cover topics in graph theory, algebra, combinatorics, and statistics.

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