A medical experiment on tumor growth gives the following data table.



x y
61 48
95 76
97 82
101 95
115 118


The least squares regression line was found. Using technology, it was determined that the total sum of squares (SST) was 2640.8 and the sum of squares of regression (SSR) was 2429.8. Calculate R2, rounded to three decimal places.

Provide your answer below:

Answers

Answer 1

The calculation of the coefficient of determination, or rounded to three decimal places is 0.080.

What is the coefficient of determination (R²)?

The coefficient of determination, R², is a statistical measurement that determines the proportion of variance in the dependent variable that the independent variable can explain.

In other words, shows how well the actual data is approximated by the regression line.

R-Squared (R²) is widely used to predict future outcomes and for hypothesis testing because it provides information about the goodness of fit of the statistical model.

x         y

61      48

95     76

97     82

101    95

115    118

The total sum of squares (SST) = 2640.8

The sum of squares of regression (SSR) = 2429.8

R² = 1 - SSR/SST

R² = 1 - 2429.8/2640.8

R² = 1 - 0.92

R² = 0.080

R² = 8%

Thus, with R² = 8%, we can conclude that the y values are only accountable for 8% of the variation in x.

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Related Questions

The sugar sweet company needs to transport sugar to market. The graph below shows the transporting cost (in dollars) versus the weight of sugar being transported (in tons) a.)What is the cost of transporting 0 tonsb.) What is the cost of transporting 1 tons c.) Hos much does the cost increase for each ton of sugar being transported d.) Are the amounts given in parts b. and c. equal?

Answers

The cost of transport of tons is the point of intersection between the line and the X axis

Now we see that the point O tons, corresponds in the line to the point Y=1600

this the answer a)

For answer b) the point 1 corresponds to 2000

for answer c) the cost increase per ton is 400 , that is because 2000-1600= 400, and the line is inclined with a slope equal to 1

Round to the nearest thousand to estimate the difference between 7,333 and 4,983

Answers

Rounded to the nearest thousand the given numbers are:

[tex]\begin{gathered} 7,333 \\ 3<5\colon Round\text{ by leaving the digit in thousand position} \\ \\ 7,333\approx7,000 \end{gathered}[/tex][tex]\begin{gathered} 4,983 \\ 9>5\colon\text{ Round increasing the digit in thousand position} \\ \\ 4,983\approx5,000 \end{gathered}[/tex]

Estimate the difference between 7,000 and 5,000:

[tex]7,000-5,000=2,000[/tex]Estimated difference: 2,000

A music store has 40 trumpets, 39 clarinets, 24 violins, 51 flutes, and 16 trombones in stock. Write each ratio in simplest formTrumpets to violins

Answers

SOLUTION

Given the question in the question tab, the following are the solution steps to get the ratio of Trumpets to violins

Step 1: Write the given data

40 trumpets

39 clarinets

24 violins

51 flutes

16 trombones

Step 2: Write the ratio of trumpets to violins

Trumpets=40

Violins=24

[tex]\begin{gathered} \text{ratio}=40\colon24=\frac{40}{24} \\ By\text{ s}implification, \\ \frac{40}{24}=\frac{5}{3} \end{gathered}[/tex]

Hence, the ratio of trumpets to violin in its simplest from is:

[tex]5\colon3[/tex]

The ages of 12 selected participants in a Students’ Congress are:

16, 24, 23, 20, 12, 27, 19, 25, 21, 23, 14, 13

What is the mean age of the participants?

Answers

The mean age of the 12 participants in a student congress is 19.75.

given 16,24,23,20,12,27,19,25,21,23,14,13
Mean generally means average. The formula of Mean is as follows

Mean = The sum  of the numbers divided by total values in set
MEAN = SUM OF ALL VALUES
               TOTAL VALUES IN SET

Add the given numbers 16+24+23+20+21+27+19+25+21+23+14+13 = 237
Divide the total number by the number of participants that is
237/12 = 19.75

The mean age of the participants = 19.75

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4x squared- 5x +4-(9x squared +3x -1)

Answers

hello

the question here requires the subtraction of polynomials

[tex]\begin{gathered} 4x^2-5x+4 \\ - \\ 9x^2+3x-1 \end{gathered}[/tex]

if we are to do this, we have to subtract the polynomials based on their degree

this would be equal to

[tex]-5x^2-8x+5[/tex]

the above polynomial is the result after subtraction, but we can as well, decide to multiply through by -1, to make or eilimate the negative sign on the second degree polynomal

[tex]\begin{gathered} (-5x^2-8x+5)\times-1 \\ = \\ 5x^2+8x-5 \end{gathered}[/tex]

You want to buy a $364,000 home. You plan to pay 5% as a down payment, and take out a 30 year loan for the rest. (Enter numeric answers to 2 decimal places.)

a) How much is the loan amount going to be?

Answers

Considering buying a home for $364,000 and paying 5% down payment.  The amount to be paid for loan is going to be $345 800

How to find the loan amount

The following is gotten from the question:

cost of the home = $ 364 000

percentage to pay as down payment = 5 %

Solving for the down payment

The down payment refers to the initial payment and is a percentage, We convert the percentage to decimal as follows

5 % = 5 / 100

= 0.05

The percentage of the money is calculated by multiplying as follows

5 % of $364 000

= 0.05 * 364 000

= $18 200

Solving for the loan amount

The loan amount is calculated by subtracting the down payment from  the cost of home

= cost of the home - down payment

= $ 364 000 - $ 18 200

= $ 345 800

Conversion from percentage to decimal followed by multiplication helped to get the down payment, then subtracting the down payment from  the cost of home helped to get the loan amount to be $345 800

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The diamond method for factoring: Fill in the missing value

Answers

Consider a quadratic expression, let "m" and "n" represent the factors.

The diamond method of factoring is the following:

On the left of the diamond, there is one of the factors, for example, "m", of the right of the diamond you will find the other factor "n".

On the top of the diamond, you will find the product of both factors, on the bottom of the diamond you will find the sum of the factors.

Looking at the given diamond, you know the result of the product and the sum of both factors:

[tex]m*n=-15[/tex][tex]m+n=14[/tex]

Using these expressions, you can find both factors.

- First, write the second expression for one of the variables, for example, for "n"

[tex]\begin{gathered} m+n=14 \\ m=14-n \end{gathered}[/tex]

- Second, replace the expression obtained on the second equation:

[tex]\begin{gathered} m*n=-15 \\ (14-n)n=-15 \end{gathered}[/tex]

Distribute the multiplication

[tex]14n-n^2=-15[/tex]

Zero the expression and order the terms from greatest to least:

[tex]\begin{gathered} 14n-n^2+15=-15+15 \\ 14n-n^2+15=0 \\ -n^2+14n+15=0 \end{gathered}[/tex]

- Third, use the quadratic expression to determine the possible values of n:

[tex]x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]

Where

a is the coefficient of the quadratic term

b is the coefficient of the x-term

c is the constant

For the quadratic expression obtained, where "n" represents the x-variable.

[tex]-n^2+14n+15=0[/tex]

The coefficients are:

a= -1

b=14

c=15

[tex]\begin{gathered} x=\frac{-b\pm\sqrt{b^2-4ac}}{2a} \\ n=\frac{-14\pm\sqrt{14^2-4*(-1)*15}}{2*(-1)} \\ n=\frac{-14\pm\sqrt{196+60}}{-2} \\ n=\frac{-14\pm\sqrt{256}}{-2} \\ n=\frac{-14\pm16}{-2} \end{gathered}[/tex]

Solve the sum and difference separately to determine both possible values for "n"

→Sum:

[tex]\begin{gathered} n=\frac{-14+16}{-2} \\ n=\frac{2}{-2} \\ n=-1 \end{gathered}[/tex]

→Difference:

[tex]\begin{gathered} n=\frac{-14-16}{-2} \\ n=\frac{-30}{-2} \\ n=15 \end{gathered}[/tex]

- Finally, determine the possible value/s of m:

For n=-1

[tex]\begin{gathered} m+n=14 \\ m+(-1)=14 \\ m-1=14 \\ m=14+1 \\ m=15 \end{gathered}[/tex]

For n=15

[tex]\begin{gathered} m+n=14 \\ m+15=14 \\ m=14-15 \\ m=-1 \end{gathered}[/tex]

So, the factors are -1 and 15 and the diamond is:

What is the slope is a line that is perpendicular to the graph of y=2x+5Mark only one oval -1/21/22-2

Answers

Step 1

Given;

[tex]y=2x+5[/tex]

Required; To find the slope.

Step 2

[tex]\begin{gathered} y=mx+c \\ m_1=slope=2 \\ c=y-intercept \\ y=2x+5 \\ For\text{ perpendicular lines }m_1(m_2)=-1 \\ \end{gathered}[/tex][tex]\begin{gathered} 2(m_2)=-1 \\ m_2=-\frac{1}{2} \end{gathered}[/tex]

Answer;

[tex]slope\text{ of the perpendicular line required=}-\frac{1}{2}[/tex]

Can someone pls help me . Thank you so much .FIRST PROBLEM

Answers

Answer:

Step-by-Step explanation:

We are given the following equation:

Given the parametric equations x = 7cos θ and y = 5sin θ, which of the following represents the curve and its orientation?

Answers

We have the following parameters

[tex]\begin{gathered} x=7cos\theta \\ y=5sin\theta \end{gathered}[/tex]

the general equation of a circle with center (0,0) is the following,

[tex]x^2+y^2=r^2[/tex]

Let's use the following tigonometric identity,

[tex]sin^2\theta+cos^2\theta=1[/tex]

solving for cos and sin in the equations we are given,

[tex]cos\theta=\frac{x}{7},sin\theta=\frac{y}{5}[/tex]

replace,

[tex](\frac{y}{5})^2+(\frac{x}{7})^2=1[/tex]

Since we have two different numbers in the denominator, this is not a circle equation but an elipse, of the form,

[tex]\frac{y^2}{a^2}+\frac{x^2}{b^2}=1[/tex]

where,

a is the vertex and,

b is the covertex

thus, in the x axis, the vertex is 7 and the y-axis the covertex is 5

Now, let's determine the direction by replacing

when Θ = 0 , then x = 7*cos0 = 7*1 = 7 , and y = 5*sin0 = 5*0 = 0

when Θ = 90° or π/2 , then x = 7*cos90° = 7*0 = 0 , and y = 5sin90° = 5*1 = 5

If we draw this, we can see that the direction is counterclockwise as in the bottom right image.

Is the function y= –10x10–10 linear or nonlinear?

Answers

The function y = -10*x¹⁰ - 10

Is not a linear function, as we can see the exponent is 10.

Is the function linear or non-linear?

Remember that a linear function is of the form:

y = m*x + b

Where x is the variable.

So a linear function is a polynomial of degree 1.

Particularly, here we have the function:

y = -10*x¹⁰ - 10

So we have an exponent of 10, which means that this is not a linear function.

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Freiese Um Which of the following is the graph of F(x) = 3x2 ?

Answers

To determine which is the graph of the function we can give some values to x to find point through the graph.

If x=0 then we have:

[tex]\begin{gathered} F(0)=3(0)^2 \\ F(0)=0 \end{gathered}[/tex]

This means that the graph passes through the point (0,0).

If x=1 then we have:

[tex]\begin{gathered} F(1)=3(1)^2 \\ F(1)=3(1) \\ F(1)=3 \end{gathered}[/tex]

This means that the graph passes through the point (1,3)

If x=-1 then we have:

[tex]\begin{gathered} F(-1)=3(-1)^2 \\ F(-1)=3(1) \\ F(-1)=3 \end{gathered}[/tex]

This means that the graph passes through the point (-1,3)

Hence we conclude that the graph has to pass through the points (0,0) (1,3) and (-1,3)

Looking at the graphs given we notice that the third graph fullfils these condition; therefore, the graph of the function is shown in option C

i neeeeeeeeeeed the aseer :D

Answers

Answer:

Step-by-step explanation:

21

The scatter plot shows the number of CDs in millions that were sold from 1999 to 2005. Use the points (1999,940) and (2002,805) to find a line of fit for the data. Then use the line of fit to estimate the number of CDs that were sold in 2008

Answers

Based on the given points from the scatter plot on the number of CDs sold in millions, the line of best fit for the data is y = -45x + 90,895

The estimated number of CDs sold in 2008 was 535 CDs.

How to find the line of best fit?

The line of best fit will take the form:
y = Slope(x) + y intercept

The value of x will be assumed to be the number of years since 1999.

The slope is:

= Change in y / Change in x

= (805 - 940) / (2002 - 1999)

= -45

The y intercept is:
940 = -45(3) + y

y = 90,895

The line of best fit is:

y = -45x + 90,895

This means that the number of CDs sold in 2008:

= -45(2008) + 90,895

= 535 CDs

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please help figure out this problem i’m trying to determine if the lines that appear to be tangent are tangent

Answers

Suppose that the two lines that form the missing angle are tangents to the circle. Then, the measure of the missing angle can be found using the following equation:

[tex]\measuredangle ABC=\frac{arc\text{ AEC - arc AGC}}{2}[/tex]

Notice that we can complete the information about the arcs of the circle with the central angle:

then, we can find the angle x with the following expression:

[tex]\begin{gathered} \measuredangle x=\frac{243-117}{2}=\frac{126}{2}=63 \\ \Rightarrow\measuredangle x=63\degree \end{gathered}[/tex]

therefore, the measure of the missing angle is 63 degrees.

Determine the a coordinates of the critical points/numbers for the function f(x)= x/x^2+5
○ x=0, x= -√5, and x = √5
○ x=0
○ No critical points
○ x = √5
○x= -√5 and x = √5

Answers

The critical points for the given function f(x) are -√5 and √5.

so option d is the correct answer.

What is the critical point?

A critical point is the part of the domain of a function where the derivative is either equal to zero or the function is not differentiable.

Differentiate the given function f(x)=x/(x²+5)

f'(x)=((x²+5)-x(2x))/(x²+5)²

Using the Quotient Rule for differentiation.

What is Quotient Rule?

A method for finding the derivative or differentiation of a function that is given as a ratio or division of two differentiable functions in calculus is known as the quotient rule.

We get f'(x)=5-x²/(x²+5)²

So the derivative is zero at -√5 and √5 and non differentiable at -√5

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Jeremy Sold x tickets for a fundraiser. Kelly sold twice as many tickets as Jeremy Altogether. Jeremy and Kelly sold 192 tickets which equation could be used to determine how many tickets Jeremy sold?

Answers

If x represents Jeremy's sold tickets, then the expression 2x + x represents the part Kelly sold twice as many tickets as Jeremy.

If the sold 192 tickets together, then the expression is 3x = 192.

Hence, the answer is B.

Use the standard algorithm to solve the equation 36 x 25 =

Answers

Answer: 900

Step-by-step explanation:

Column method

A basket can hold 40 apples. Justin has 22 apples. He plans to buy 7 more. Each apple costs $1.buys the new ones, how many more apples will the basket hold?The basket can hold 15 more apples after Justin buys more.

Answers

Answer

Explanation

The basket can hold a maximum of 40 apples.

Justin currently has 22 apples. He plans to buy

The diameter of the pool is 5 feet. What is the circumference of the pool?

Answers

The circumference is 15.7 feet

what is 5/8 out of 100

Answers

5/8 of 100 can be obtained by applying the rule of three:

[tex]\begin{gathered} 1\text{ ----- 100} \\ 5/8\text{ ----x} \end{gathered}[/tex]

then, x is given by

[tex]\begin{gathered} x=\frac{\frac{5}{8}\cdot100}{1} \\ x=62.5 \end{gathered}[/tex]

then, the answer is 62.5.

Find the equation (in slope-intercept form) of the line passing through the points with the given coordinates.(3,-5) , (4,5)

Answers

We will determine th equation in slope-intercept from of the line as follows:

First, we find the slope:

[tex]m=\frac{5-(-5)}{4-(3)}\Rightarrow m=10[/tex]

Then:

[tex]y-5=10(x-4)\Rightarrow y-5=10x-40[/tex][tex]\Rightarrow y=10x-35[/tex]

So, the equation of the line in slope-intercept form is:

[tex]y=10x-35[/tex]

A bridge being designed will crossthe river at a right angle. Theequation of the left bank of theriver is y = 2x + 8. The center ofthe bridge will pass through (0, 2).What is the equation of the linerepresenting the bridge?

Answers

Let's begin by listing out the information given to us:

Left side: y = 2x + 8

Center of the bridge: (0, 2)

[tex]\begin{gathered} y=2x+8 \\ m=2 \\ \text{However, the bridge is perpendicular to }y=2x+8\colon \\ m(perpendicular)=-\frac{1}{m} \\ m(perpendicular)=-\frac{1}{2} \end{gathered}[/tex]

Use the point-slope formula to get the equation of the bridge:

[tex]\begin{gathered} y-y_1=m(x-x_1) \\ (x_1,y_1)=(0,2);m=m(perpendicular)=-\frac{1}{2} \\ y-2=-\frac{1}{2}(x-0) \\ y-2=-\frac{1}{2}x \\ y=-\frac{1}{2}x+2 \\ \\ \therefore\text{ equation of the line representing the bridge is }y=-\frac{1}{2}x+2 \end{gathered}[/tex]

write the slope intercept form:through: (2, 5), perp. to y= -5

Answers

If the original line is y = -5, then the perpendicular line would be x = a, where a is the x value of the point where it passes through, then the line is x = 2

Answer:

x = 2

Solve the system of equations. If the system has no solution say that it's inconsistent. [tex]\begin{gathered}x + 5y = 2 \\ 3x + 15y = 6\end{gathered}[/tex]

Answers

Answer:

Explanation: Given the system of equations:

[tex]\begin{gathered} x+5y=2 \\ 3x+15y=6 \end{gathered}[/tex]

A number times the sum of 12 and 32 (write as an algebraic expression)

Answers

ANSWER

x(12 + 32)

EXPLANATION

Let x be 'the number'.

A number times... means 'a number multiplied by...'

The sum of 12 and 32 is (12 + 32)

The complete algebraic expression is x(12 + 32)

1. As part of a summer internship, five people -- Cindy, Damaris, Eugenio, Fareed, and Guzal -- are to be assigned to floors 1-5 in a dormitory. Each person will occupy his or her own entire floor and no other people will be in the dormitory. The assignment of people to floors must follow the following rules:Eugenio lives immediately above Damaris.Cindy is not on the first floor.Fareed does not live immediately below Damaris.Guzal lives either on the first floor or the fifth floor.Which one of the five people could be assigned to live on any of the five floors in the dormitory? A. Cindy B. Damaris C. Eugenio D. Fareed E. Guzal2. If Fareed lives neither directly above nor directly below Cindy in the dormitory, which one of the following people must live on the fourth floor? A. Cindy B. Damaris C. Eugenio D. Fareed E. Guzal

Answers

SOLUTION

(1) From the question, if Eugene lives immediately above Damaris, then Eugene can only live between floors 1 to 4.

And Damaris can only live between floors 2 to 5.

Guzal can only live on floors 1 or 5

Siince Cindy cannot live on the first floor, she can only live between floors 2 to 5, Since Fareed does not live immediately below Damaris. Fareed can live between floors 1 to 5.

Hence the answer is Fareed, option D

Writing about Finding a Percen Explain how to find 27% of 16 using multiplication by a decimal. Then explain how to use estimation to check your answer.

Answers

To find 27% of 16 using multiplication by a decimal, we can proceed as follows:

First, convert the number 27 in decimal:

[tex]16\cdot\frac{27}{100}=16\cdot0.27=4.32[/tex]

A way to estimate the possible value, we can multiply the number 16 by the nearest tenth, that is, 0.3. We know that the possible value is a little greater than the actual value.

We can do this in the following way:

[tex]16\cdot\frac{30}{100}=\frac{48}{100}=4.8[/tex]

Then, after the estimation, we can say that the value must be less than 4.8. Multiplying by 3 or 30 is easier than by 27. This is a way to check the answer.

We can also say that if we multiply 16 by 3 is 48 (equivalently to 4.8, after doing the correct operations), and this is a quick value to know, that, approximately 4.32 is 27% of 16.

which is the solution of 3(t + 1) = 6 - 13.5?A <-5.5B t2-5.5Ci< 5.5D (>55

Answers

Let's begin by identifying key information given to us:

[tex]\begin{gathered} 3\mleft(t+1\mright)\le6t-13.5 \\ 3t+3\le6t-13.5 \\ \text{Put like terms together, we have:} \\ 3+13.5\le6t-3t \\ 16.5\le3t \\ \frac{16.5}{3}\le\frac{3t}{3} \\ 5.5\le t\Rightarrow t\ge5.5 \\ \therefore t\ge5.5 \end{gathered}[/tex]

Therefore, D is the correct answer

"∆ABC~∆DEF. The area of ∆ABC is given. Find the area of ∆DEF. Do not lable the final answer."

Answers

In this case, we'll have to carry out several steps to find the solution.

Step 01:

Data

∆ABC~∆DEF

triangle 1:

AC = 10

area = 65 in²

triangle 2:

DF = 20

area = ?

Step 02:

We must apply the rules of similar triangles to find the solution. .

[tex]\frac{triangle\text{ 1 AC}}{\text{triangle 2 DF }}=\frac{triangle\text{ 1 area}}{\text{triangle 2 area}}[/tex][tex]\frac{10}{20}=\frac{65in^2}{triangle\text{ 2 area}}[/tex]

triangle 2 area * 10 = 65 in² * 20

triangle 2 area = (65 in² * 20 ) / 10

= 130 in²

The answer is:

The area of the big triangle is 130 in² .

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