sorry for this being so long I'm a rush but ask questions pls.
Step-by-step explanation:
The question specifies ranges of possible lengths and masses. The length can vary from about 19.5 millimeters to almost 20.5 millimeters. The mass can vary from about 99.5g to almost 100.5g.
For more about my use of the terms about and almost, and the reason for the “.5” values, see the Notes at the end.
Now:
A smaller object with a given mass will have a higher density;
A larger object with a given mass will have a lower density;
An object of given size with a smaller mass will have a lower density;
An object of given size with a larger mass will have a higher density.
This could be summed up by saying that density varies inversely with size but varies directly with mass.
So the lowest density occurs with the largest length and the smallest mass, while the highest density occurs with the smallest length and the largest mass.
Within the bounds of error, the largest possible length is about 20.4999…mm while the smallest possible mass is 99.5g. So doing the density calculation with these numbers will give the lowest possible density.
Similarly, doing the density with a length of 19.5mm and mass of 100.4999…g will give the largest possible density within the error bounds.
Notes
The first issue is with the term “accurate to the given millimeter”. My interpretation follows the guidelines in Illustrative Mathematics (under Solution) and appears, from the text in that page, to be consistent with the Common Core (which is the way we teach math to kids these days in the U.S.)
In the context of measuring the diameter of a circle, it says:
Juan finds that the circle is 5 cm or 50 mm in diameter. Since the tape measure is accurate to the nearest millimeter, this means that the actual diameter is between 4.95 centimeters and 5.05 centimeters.
There’s a deeper issue associated with rounding. The most common rule is that 0.5 rounds up. Thus the quote above is not quite correct; the actual diameter is between 4.95 centimeters and just less than 5.05, but not 5.05 exactly which would round to 5.1 centimeters.
The example in the linked page probably doesn’t deal with this subtle issue because it’s for kids who have not yet been taught about things like repeating decimals or the conceptual complexity of perfect rounding. I dealt with it by specifying “…” in the values above.
Working her way through college kathy works two part time jobs for a total of 22 hours a week. job a pays $6.20 per hour, and job b pays $6.50 per hour. how many hours did she work at each job the week that she made $140.60? (round to two decimal places if necessary.)
Using Algebraic equation, Kathy worked 22 hours at job A and 12 hours at job B, the week she made US $ 140.60.
Let's review all the information given for solving this question:
Rate per hour of Job A = US$ 6.20
Rate per hour of Job B = US$ 6.50
Earnings received by Kathy during the week = US$ 140.60
Total time worked by Kathy during the week = 22hours
Hours at job A = x
Hours at job B = 22 -x
In order to find how many hours Katy worked at each job: This is the Algebraic equation that we'll use:
6.20x + 6.50 (22 - x) = 140.60
6.20x + 143- 6.50x = 140.60
-0.3x = 140.60 - 143
-0.3x = - 2.4
x = -(2.4)/-(0.3)
x = 14.3/0.3 = 8 (Dividing by 0.3 at both sides)
Kathy worked 8 hours at job A.
Hours at job B = 22 - x. Put x = 11 we get
Hours at job B = 22 -11
= 11
Hence, using Algebraic equation Kathy worked 22 hours at job A and 12 hours at job B, the week she made US $ 140.60.
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(i) in order to play a game of basketball, 15 children at a playground divide themselves into team a, b and c of 5 each. how many different divisions are possible? (ii) if the teams are not distinguishable, how many different divisions are possible?
(i) The number of different divisions possible when 15 children divide themselves into teams of 5 each (Team A, B, and C) is 756.
(ii) If the teams are not distinguishable, the number of different divisions possible is 756 divided by 3!, which equals 126.
Find the number of different divisions?(i) To determine the number of different divisions when 15 children divide themselves into three teams of 5 each, we can calculate the number of combinations.
Since the order of the teams does not matter, we use the combination formula.
The formula is nCr = n! / (r! * (n - r)!), where n is the total number of children and r is the number of children per team.
Plugging in the values, we have 15C5 * 10C5 = (15! / (5! * 10!)) * (10! / (5! * 5!)) = 756.
(ii) If the teams are not distinguishable, we need to account for the fact that the order of the teams doesn't matter.
Each division would be counted multiple times if we considered the teams distinguishable. Since there are 3! (3 factorial) ways to arrange the teams, we divide the previous result by 3!, which gives us 756 / 3! = 126.
This accounts for the different arrangements of the same teams and gives us the number of distinct divisions.
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I need help I have been struggling with this question for 15 minutes
The seats in a movie theater are arranged so that each row has 6 more seats than the row in front of it. If the first row has 24 seats, how many seats are in the 6th row?
a. 30
b. 48
c. 54
d. 60
Answer:
54 seats
Step-by-step explanation:
To make it easier, I'll put it like this.
Row | Seats
1 | 24
2 | 30
3 | 36
4 | 42
5 | 48
6 | 54
(Add 6, because each row has 6 more seats than the row in front of it.)
So, the 6th row has 54 seats.
Hope this helped !
Miguel went for a drive in his new car. He drove at a speed of 53 miles per hour for 84.8 miles
Time taken by Miguel car to drive is, 1.6 hour.
What is Division method?Division method is used to distributing a group of things into equal parts. Division is just opposite of multiplications. For example, dividing 20 by 2 means splitting 20 into 2 equal groups of 10.
We have to given that;
Miguel went for a drive in his new car. He drove at a speed of 53 miles per hour for 84.8 miles.
We know that;
⇒ Speed = Distance / Time
⇒ Time = Distance / Speed
Here, Speed = 53 miles per hour
Distance = 84.8 miles
Hence, We get;
⇒ Time = 84.8 / 53
⇒ Time = 1.6 hour
Thus, Time taken by Miguel car to drive is, 1.6 hour.
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Write in standard form
61500
Answer:
6.15*104
Step-by-step explanation:
Suppose we could multiply two 3 × 3 matrices using 25 scalar multiplications and a constant number of scalar additions and subtractions. Set up and solve the recurrence relations to analyze the resulting divide-and-conquer algorithm for matrix multiplication.
The resulting divide-and-conquer algorithm for matrix multiplication using 25 scalar multiplications and a constant number of scalar additions and subtractions is efficient for multiplying two 3 × 3 matrices.
To analyze the divide-and-conquer algorithm for matrix multiplication, let's set up and solve the recurrence relations based on the given conditions.
Let's assume we have two 3 × 3 matrices A and B, and we want to compute their product C = A × B.
According to the given information, we can perform the matrix multiplication using 25 scalar multiplications and a constant number of scalar additions and subtractions.
In a divide-and-conquer algorithm, we can split the matrices into smaller submatrices to simplify the multiplication process. Let's assume we divide the matrices into 2 × 2 submatrices:
A = [A11 A12]
[A21 A22]
B = [B11 B12]
[B21 B22]
C = [C11 C12]
[C21 C22]
The recurrence relation for this algorithm can be expressed as follows:
C11 = A11 × B11 + A12 × B21
C12 = A11 × B12 + A12 × B22
C21 = A21 × B11 + A22 × B21
C22 = A21 × B12 + A22 × B22
Since each entry of matrix C requires a scalar multiplication and there are four entries in total, we have a total of 4 scalar multiplications.
To solve the recurrence relation, we can express the number of scalar multiplications as a function of the subproblem size. In this case, the subproblem size reduces to 2 × 2 matrices, and the number of scalar multiplications can be considered constant.
Therefore, the resulting divide-and-conquer algorithm for matrix multiplication using 25 scalar multiplications and a constant number of scalar additions and subtractions is efficient for multiplying two 3 × 3 matrices.
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10x + 8 = 3(x - 2)
10x + 8 = 3x
Answer:
1) -2
2) 8/7
Step-by-step explanation:
1) 10x+8=3(x-2)
10x+8=3x-6
10x-3x=-6-8
7x=-14
x=-2
2) 10x+8=3x
10x-3x=8
7x=8
x=8/7
Hope it helps
a recent survey reported that small businesses spend 24 hours a week marketing their business. a local chamber of commerce claims that small businesses in their area are not growing because these businesses are spending less than 24 hours a week on marketing. the chamber conducts a survey of 58 small businesses within their state and finds that the average amount of time spent on marketing is 22.7 hours a week. assuming that the population standard deviation is 6.1 hours, is there sufficient evidence to support the chamber of commerce’s claim at the 0.02 level of significance?
chamber of commerce’s claim at the 0.02 level of significance, z = -1.75
What is z test?
If the data is distributed normally, a z test can be used to determine whether the means of two populations differ from one another. The z test statistic's value must be determined, together with the null hypothesis and alternative hypothesis setups, for this reason. On the z critical value, the decision criterion is based. The distribution graph is divided into acceptance and rejection zones during hypothesis testing by the z critical value. The null hypothesis can be rejected if the test statistic lies inside the rejection region; otherwise, it cannot.
a recent survey reported that small businesses spend 24 hours a week marketing their business.
these businesses are spending less than 24 hours a week on marketing. the chamber conducts a survey of 58 small businesses within their state and finds that the average amount of time spent on marketing is 22.7 hours a week.
assuming that the population standard deviation is 6.1 hours.
Given n = 93, u =24, x' = 23, α=5.5
z = x'- u / α(/√n) = (23-24/5.5/√5) = -1.75
Hence, chamber of commerce’s claim at the 0.02 level of significance, z = -1.75
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Rico paid $180 sales tax on his new $2,400 motorcycle. What was the sales tax percentage rate where he bought his motorcycle?
Answer:
it is 7.5 rate
Step-by-step explanation:
I used a calculator to get the answer and it is correct.
These tables correspond to inputs and outputs. Which of these input and output tables could represent a function rule, and which ones could not?
Table A and Table C is a function. Table B and Table D is not a function.
What is a function?A function can be defined as the outputs for a given set of inputs.
The inputs of a function are known as the independent variable and the outputs of a function are known as the dependent variable.
We know that a relation is a function if it is one-to-one or many-to-one.
But a relation is not a function if it is many.
Table A; It is a function and it is a many-to-one function.
Table B; It is not a function as input 1 leads to two different outputs 1, - 1.
Table C; It is a function and it is a one-to-many function.
Table D; It is not a function as one input leads to 3 different outputs.
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Mary has borrowed 48 books from the library. This is 22% of all of the books in the library. How many books are in the library?
Answer:
218
Step-by-step explanation:
ATQ,
22%of total books = 48
Let the total no. of books in library be x.
22/100x=48
x=4800/22
X=218(approximately)
help me please i need your help
Answer:
∞
Step-by-step explanation:
I don’t know just think it out. That is the explaination
This table shows the music preferences in 14- to 19-year-olds. A Circle Graph was made using this data and presented at a conference.
What could make people at the conference draw wrong conclusions from this Circle Graph?
A. The Country section has the smallest area.
B. The Rap section covers the largest area.
C. The Alternative section is larger than the rock and roll section.
D. The Classical section is not included in the Circle Graph.
The wrong conclusions that can be drawn from the circle graph are:
The Country section has the smallest area.
The Classical section is not included in the Circle Graph.
What is a circle graph?A circle graph is a graph that displays information in a circle. The circle is divided into slices which represent a numerical proportion. The sum of angles in a pie chart is 360 degrees
In the circle graph, the country section has a percentage of 10% while the classical section has a percentage of 2%.
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Answer:
the answer is D
Step-by-step explanation:
look at the table there are 5 music genres but there's only 4 on the circle graph.
Average rate of exchange
50 points for answer and brainliest
Average rate of change of the function F (x ) = 9/ -2 (x)-7. Average rate is -3, 9
Explain about the Average rate?The average rate at which one quantity changes in relation to another's change is referred to as the average rate of change function. A method that determines the amount of change in one item divided by the corresponding amount of change in another is known as an average rate of change function.
Divide the change in y-values by the change in x-values to determine the average rate of change. In order to determine changes in measurable parameters like average speed or average velocity, finding the average rate of change is extremely helpful.
f (x ) = -2
f (x) = 9/ -2 (-2)-7
= 9 / 4 - 7
=9 / -3
= -3
f (x ) = -4
f (x) = 9/ -2 (4)-7
= 9 / 8 - 7
=9 / 1
= 9
Average rate is -3, 9
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questions in screenshot (odd numbers only)
Answer:
1. 250x12= 3000. So she earned $3000 in that 12 weeks, if you include the 500 then it would be 3500 dollars if not then it would be 3000 dollars.
2. Divide 75 and 12 and you get 6.25 if you want to estimate. Then the answer would be, all of the fields will be harvested in just 6 days.
3. Divide 54 and 3 and you get 18. 18 weeks if they frame the sanem number each week.
4. If you divide 8,000 and 450 you get 17.7777777778. If you want to estimate then the it would be 18. So it would take about 18 days to fill up the 8,000 gallons of water.
5. This graph is y=20x
6. Don't really know, if the 0 is 360 then 10 and 300 are pretty easy because 10=30. so 0, 10, 20 is 360, 300,240 likes the graph and I would think you can solve this
How fast does Santa's sleigh travel how fast would Santa have to travel to get to every house in the UK in m/s the average distance between houses in the UK is 50m and there are 25 million homes he manages this in 12 hours
Answer:
First of all he goes throughout the whole WORLD so UK would take an average of 30 an hour. Santa would travel an approx. of 650 mph per second
Step-by-step explanation:
78 miles per household, a total trip of 75-1/2 million miles, not counting stops to do what most of us must do at least once every 31 hours, plus feeding and etc. This means that Santa's sleigh is moving at 650 miles per second, 3,000 times the speed of sound.
A survey was given to a random sample of 400 residents of a town to determine whether they support a new plan to raise taxes in order to increase education spending. Of those surveyed, 168 respondents said they were in favor of the plan. Determine a 95% confidence interval for the proportion of people who favor the tax plan, rounding values to the nearest thousandth.
What is the 100th digit of pi?what is the hundredth digit of pi? this would include the 3 in the beginning.
100th digit of the pi is 7
Pi (represented by the Greek letter π) is a mathematical constant that represents the ratio of the circumference of a circle to its diameter. It is approximately equal to 3.14159,
The decimal representation of pi (π) is an infinite non-repeating sequence of digits, so there is no simple formula or algorithm to determine the value of its digits. However, you can use a computer program or online tool to calculate the digits of pi to a certain number of decimal places.
Assuming you are looking for the 100th decimal digit of pi, it is 7. This means that if you write out the first 100 digits of pi, the 100th digit is 7.
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find the first four terms of the sequence given by the following
Answer:
42, 38, 34, 30
Step-by-step explanation:
You want the first 4 terms of the sequence described by ...
an = 42 -4(n -1), n ∈ ℕ
Arithmetic sequenceYou can write the first 4 terms of the sequence by evaluating the 'an' expression for n = 1, 2, 3, 4.
Or, you can recognize the expression describes a sequence with a first term of 42 and a common difference of -4. That is, each term is 4 less than the one before.
The terms you want are ...
42, 38, 34, 30
__
Additional comment
The equation for the n-th term of an arithmetic sequence is ...
an = a1 +d(n -1)
where a1 is the first term, and d is the common difference. Comparing this to the given equation, we see a1 = 42, d = -4.
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WRITE A EQUATION ''THE QUOTIENT OF A NUMBER AND 20.7 is 9
Answer:
n ÷ 20.7 = 9
Step-by-step explanation:
Let n be the unknown number
Quotient is division and is means equals.
n ÷ 20.7 = 9
Hey everyone, can you please help me with this question? THANKS!
Answer:
6 granite, 3 marble, 14 sandstone, 1 slate
ratio of sandstone to marble
how many sandstone does she have .....14
how many marble does she have......3
so the ratio would be 14:3
Answer:
C. 14:3
Step-by-step explanation:
Dana has 14 pieces of sandstone.
Dana has 3 pieces of marble.
The ratio of pieces of sandstone to pieces of marble is 14:3.
The ratio cannot be simplified further.
Increase 56 by 13% give your answer as a decimal
Answer: 63.28
Step-by-step explanation:
To increase a number by a certain percentage, you can multiply the number by (1 + the percentage as a decimal). In this case, you would multiply 56 by 1.13 to find the result.
56 * 1.13 = 63.28
So, if you increase 56 by 13%, the result is 63.28. The decimal representation of this number is 0.6328.
the answer should be 63.28 if its wrong then i don't know what it is.
Answer the question in the image below
Answer:
ans of an 1 is option b
Step-by-step explanation:
because x and y both are +ve
Each triangle in the STL file is defined by the vertices and inward pointing surface normal vector True O False Since the STL file is created from the Solid Model, it can be reconverted into the original CAD model O True False Which one of the following is NOT an advantage of using lattice structure? Reducing the weight Saving the material cost Simplifying the design and manufacturing process Increasing the heat exchange area for a heat exchanger
False. Each triangle in the STL file is defined by the vertices, but not necessarily by the inward pointing surface normal vector. The surface normal vector is often calculated based on the vertex positions.
False. The STL file is a mesh representation of the CAD model, and it does not contain all the information needed to fully reconstruct the original CAD model. It lacks information such as parametric features, assembly relationships, and design intent, making it difficult to recreate the exact original model.
The option "Increasing the heat exchange area for a heat exchanger" is NOT an advantage of using a lattice structure. Lattice structures are known for their lightweight properties, material-saving benefits, and simplified design and manufacturing processes.
However, increasing the heat exchange area for a heat exchanger is not typically associated with lattice structures. Heat exchangers usually rely on other design considerations, such as fin arrays or extended surfaces, to enhance heat transfer efficiency, rather than lattice structures.
Therefore, increasing heat exchange area is not a direct advantage of lattice structures.
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Pls help with this answer
When b is 3, the value of the expression \(2b^3 + 5\) is 59.
To evaluate the expression\(2b^3 + 5\) when b is 3, we substitute the value of b into the expression and perform the necessary calculations.
Given that b = 3, we substitute this value into the expression:
\(2(3)^3 + 5\)
First, we evaluate the exponent, which is 3 raised to the power of 3:
2(27) + 5
Next, we perform the multiplication:
54 + 5
Finally, we add the two terms:
59
Therefore, when b is 3, the value of the expression \(2b^3 + 5\) is 59.
In summary, by substituting b = 3 into the expression \(2b^3 + 5\), we find that the value of the expression is 59.
It's important to note that the provided equation has multiple possible solutions for x, but when b is specifically given as 3, the value of x is approximately 3.78.
It's important to note that in this equation, we substituted the value of b and solved for x, resulting in a specific value for x. However, if we wanted to solve for b given a specific value of x, we would follow the same steps but rearrange the equation accordingly.
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5. Diagonalization via unitary transform. Consider a 2 x 2 matrix Ω=( cosθ
−sinθ
sinθ
cosθ
) (a) Show Ω is unitary. (b) Show its two eigenvalues are e iθ
and e −iθ
; find the corresponding eigen vectors. (Feel free to work with matrices, and choose your own phase factor for the eigen vectors.) (c) From the eigenvectors, construct the unitary matrix U so that it diagonalizes Ω, U †
ΩU=( e iθ
0
0
e −iθ
). (The columns of U are nothing but the eigenvectors of Ω. This is explained in Sakurai 1.5.3. Use this example to verify it is true.)
(a) Ω is unitary as Ω†Ω = I, where Ω† is the conjugate transpose of Ω and I is the identity matrix.
(b) The eigenvalues of Ω are e^(iθ) and e^(-iθ), with corresponding eigenvectors [1, e^(-iθ)] and [e^(iθ), 1].
(a) To show that Ω is unitary, we need to verify that Ω†Ω = I, where Ω† denotes the conjugate transpose of Ω and I is the identity matrix.
Calculating Ω†, we have:
Ω† = ( cosθ sinθ−sinθ cosθ)
Now, let's compute the product Ω†Ω:
Ω†Ω = ( cosθ sinθ−sinθ cosθ)( cosθ−sinθsinθ cosθ)
= (cos^2θ + sin^2θ cosθsinθ - sinθcosθ -sinθcosθ + cosθsinθ sin^2θ + cos^2θ)
= (1 0 0 1)
= I
Since Ω†Ω = I, we have shown that Ω is unitary.
(b) To find the eigenvalues and corresponding eigenvectors, we solve the characteristic equation:
|Ω - λI| = 0
where λ is the eigenvalue and I is the identity matrix.
Ω - λI = ( cosθ−λ −sinθsinθ cosθ−λ)
Setting the determinant of Ω - λI equal to zero, we get:
( cosθ - λ)(cosθ - λ) - (-sinθ)(sinθ) = 0
(cos^2θ - 2λcosθ + λ^2) + sin^2θ = 0
2λcosθ - λ^2 - 1 = 0
Solving this quadratic equation, we find two eigenvalues:
λ = e^(iθ) and λ = e^(-iθ)
To find the corresponding eigenvectors, we substitute each eigenvalue into the equation (Ω - λI)v = 0 and solve for v.
For λ = e^(iθ):
(cosθ - e^(iθ))v1 - sinθv2 = 0
sinθv1 + (cosθ - e^(iθ))v2 = 0
Solving these equations, we find the eigenvector v1 = [1, e^(-iθ)] and v2 = [e^(iθ), 1].
For λ = e^(-iθ):
(cosθ - e^(-iθ))v1 - sinθv2 = 0
sinθv1 + (cosθ - e^(-iθ))v2 = 0
Solving these equations, we find the eigenvector v1 = [1, -e^(iθ)] and v2 = [-e^(-iθ), 1].
(c) Constructing the unitary matrix U using the eigenvectors, we have:
U = [v1, v2] = [[1, e^(-iθ)], [e^(iθ), 1]]
To verify that U†ΩU is a diagonal matrix, we calculate:
U†ΩU = [[1, -e^(iθ)], [e^(-iθ), 1]] * [[cosθ, -sinθ], [sinθ, cosθ]] * [[1, e^(-iθ)], [e^(iθ), 1]]
= [[e^(iθ)cosθ + e^(-iθ)sinθ, -e^(iθ)sinθ + e^(-iθ)cosθ], [e^(-iθ)cosθ + e^(iθ)sinθ, -e^(-iθ)sinθ + e^(iθ)cosθ]]
= [[e
^(iθ)cosθ + e^(-iθ)sinθ, 0], [0, e^(-iθ)cosθ + e^(iθ)sinθ]]
= [[e^(iθ)cosθ, 0], [0, e^(-iθ)cosθ]]
The resulting matrix is indeed a diagonal matrix with the eigenvalues on the diagonal, as expected.
Therefore, U†ΩU = [[e^(iθ)cosθ, 0], [0, e^(-iθ)cosθ]], confirming the diagonalization of Ω.
Note: The choice of phase factor for the eigenvectors may vary, as long as they satisfy the eigenvector equations.
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Help me solve this please
Answer:
x=-3 im pretty sure
Step-by-step explanation:
so if y=4 and 4 is something plus 7, 7+-3=4 so im abut 98% its -3
Raoul collects sports cards. He has six baseball cards, three football cards, four hockey cards, and three basketball cards. What fraction of his sports cards are hockey cards?
Given information:
Raoul collects sports cards.
He has six baseball cards, three football cards, four hockey cards, and three basketball cards.
Raoul has a total of 6 + 3 + 4 + 3 = 16 sports cards.
The number of hockey cards he has is 4.
Therefore, the fraction of his sports cards that are hockey cards is:
4/16
Simplifying the fraction by dividing both the numerator and denominator by 4, we get:
1/4.
So, 1/4 of Raoul's sports cards are hockey cards.
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Ally works in a shop for $18 per hour. She is not allowed to work more than 40 hours a week but has to work at least 20 hours. State a reasonable domain for this problem.
Answer:
Hi there!
The domain is:
20<=x<=40
Step-by-step explanation:
This states that:
x>=20
x<=40
Which fits the problem!
Hope this helps
For a given function f(x) we define the domain as the set of possible values of x that we can use in the function.
Here we will find that the domain is D: [20h, 40h]
We know that Ally wins $18 per hour, and she has two restrictions:
She cant' work more than 40 hours.
She needs to work at least 20 hours.
Then her weekly salary can be written as:
s(x) = $18*x
Where x is the number of hours that she works each week.
With the above restrictions we have:
20h ≤ x ≤ 40h
Then the domain is:
D: [20h, 40h]
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