f(x)=x^2-2x+3x; f(x)=-6x

Answer and Step-by-step explanation: Standard Deviation is the measure of how diferent a number is from the mean of the data set. It is the spread of a data set. To calculate it manually:

1) Find the mean of the data set. Mean, represented by μ, is the sum of all the values divided by the total number of elements forming the set;

2) Subtract each number with the Mean and square the result;

3) Add the differences and divide it by the total number of elements of the set;

4) Take the square root of the result and that is the Standard Deviation.

The calculations can be done by a calculator like Excel:

1) In each cell of a same column, write the data you want to know the deviation.

2) On the last cell, write: =stdev.p(A1:A10) or =stdev.s(A1:A10).

3) Press Enter. The deviation will appeared on the same cell.

The function STDEV.P is used when the data represents the entire population, whereas STDEV.S is used when the data is for a sample of the population. Inside the parenthesis, put the cells where your data is. For example, if you put your data in the column A, from cell 1 to cell 10, you write like it's written above.

Answer:

72.

Step-by-step explanation:

Given a group of 6, 9 and 12.

We are to determine the least number of patties that will be shared equally among the groups.

This we do by determine the Least common multiple of the three numbers.

[tex]6=2 X 3\\9 = 3 X 3\\12 =2 X 2 X 2\\L.C.M.=2^3X3^2=72[/tex]

Therefore, the least number of patties that can be shares equally among groups of 6, 9 and 12 is 72.

Answer:

  65,280

Step-by-step explanation:

Consider the 4×4 grid ...

  [tex]\left[\begin{array}{cc}a&b\\d&c\end{array}\right][/tex]

where each of a, b, c, d is a 2×2 array of tiles. Let's use the notation a' to represent the 2×2 array "a" rotated right 1/4 turn. For 90° rotational symmetry, we must have b=a', c=b'=a'', d=c'=b''=a'''. That is, once "a" is determined, the rest of the grid is determined. Since "a" consists of 4 tiles, each of which can be black or white, there are 2^4 = 16 patterns that have 90° rotational symmetry.

The same will be true of 270° rotational symmetry, for the same reason.

__

For 180° rotational symmetry, we must have c=a'' and d=b''. Then the combination of "a" and "b" together fully determines the grid. Together, "a" and "b" consist of 8 tiles, so there are 2^8 = 256 ways to pattern the grid so it will have 180° rotational symmetry. (Of those, 16 have 90° symmetry, and 16 have 270° symmetry. The sets are overlapping.)

__

The 16 tiles of the grid can be colored 2^16 = 65,536 different ways. As we have seen, 256 of those colorings result in 180° rotational symmetry. Then the number of colorings that have no rotational symmetry is ...

  65,536 -256 = 65,280 . . . . colorings not rotationally symmetric

Answer:

5x^2+5x+3/3x^2+3x

Step-by-step explanation:

Answer:

(a) The population of interest in this situation is the average age of visitors to the park in MAY during weekdays or weekends.

(b) Two samples are described in the above situation, that is;

(c) The average age of 37 years is a statistic.

(d) The above information represents a quantitative variable.

(e) The possible explanation for the large difference in age between the two samples would be that during weekdays most of the teenagers or children below 20 years of age are not able to come to parks because of their schools, coachings or some studies related work.

Step-by-step explanation:

We are given that a research firm regularly conducts customer satisfaction surveys for an amusement park. A survey of 100 randomly selected park visitors on a weekday in May concluded the average age of visitors to the park was 37 years.

When the survey was repeated with 100 randomly selected park visitors on a Saturday in May the average age of visitors to the park was determined to be 17 years.

(a) The population of interest in this situation is the average age of visitors to the park in MAY during weekdays or weekends.

(b) Two samples are described in the above situation, that is;

(c) The average age of 37 years is a statistic as it is the sample average age of visitors to the park on a weekday, i.e. [tex]\bar X_1[/tex] = 37 years.

(d) The above information represents a quantitative variable because in this we are concerned about the average age of visitors in the park which is a numeric value and we are not interested in any qualitative aspect.

(e) The possible explanation for the large difference in age between the two samples would be that during weekdays most of the teenagers or children below 20 years of age are not able to come to parks because of their schools, coachings or some studies related work.

But during weekends like Saturday, the schools or coaching institutions are generally closed due to which they are able to come to parks to play and because of this there are large number of children below 20 years of age who visit parks on weekends.

Answer:

a. Calculate the prevalence rate of autism for these children for the two age categories.

b. Convert the prevalence rate to a rate per 1,000

Step-by-step explanation:

Generally prevalence is calculated using the following formula:

(number of people with autism / number of people measured) x 100%

age category

3-5: prevalence rate = (19/3,479) x 100% = 0.55%

6-10: prevalence rate = (17/5,417) x 100% = 0.31%

if you want to convert to a rate per 1,000, allyou need to do is multiply by 1,000 instead of 100

3-5: prevalence rate = (19/3,479) x 1,000 = 5.5

6-10: prevalence rate = (17/5,417) x 1,000 = 3.1

Answer:

c) Permutations: 40320

Step-by-step explanation:

We have that permutations are groupings in which the order of the objects matters. Combinations are groupings where content matters but order does not.

In this case, then the batting order, therefore the order does matter, therefore, it would be a permutation, where n = 8 and r = 7

nPr = n! / (n-r)!

Replacing:

8P7 = 8! / (8-7)! = 40320

Which means that the answer is c) Permutations: 40320

Answer:

Quadrilateral ABCD is a Quadrilateral with four equal sides so either a rhombus or square

But

Quadrilateral ABC'D is a quadrilateral with two adjacent sides equal so it's a kite shape

Step-by-step explanation:

(11, -7), B(9, -4), C(11, -1), and D(13, -4).

Let's take out the values of x and y coordinate with the way they are arranged

X = 11,9,11,13

Y = -7,-4,-1,-4

So we observe that distance of the coordinates on either x is 2 units and y is 3 units.

But when the the value was changed to

C′(11, 1), (11, -7), B(9, -4), C′(11, 1), and D(13, -4).

There was difference of 2 unit and 4 unit making the new shape a kite.

The diagram attached explain better

Answer:

1. rhombus with non-perpendicular adjacent sides

2. kite

Step-by-step explanation:

i just got it right on edmentum.

Please mark as brainliest.

Answer:

[tex]x\in(-2,1)[/tex]

Step-by-step explanation:

We are given that a function

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

[tex]f(x)=x^2-2x-8[/tex]

Differentiate w.r.t x

[tex]f'(x)=2x-2[/tex]

[tex]f'(x)=0[/tex]

[tex]2x-2=0[/tex]

[tex]2x=2\implies x=\frac{2}{2}=1[/tex]

Therefore, intervals

[tex](-\infty,1),(1,\infty)[/tex]

Interval :[tex](-\infty,1)[/tex]

x=0

[tex]f'(0)=-2<0[/tex]

Decreasing  function.

Interval:[tex](1,\infty)[/tex]

Substitute x=2

[tex]f'(2)=2(2)-2=2>0[/tex]

Function increasing.

From given graph we can see that function is negative for the values of x

-2<x<4

Hence, the graph is negative and decreasing for the values of x

[tex]x\in(-2,1)[/tex]

Answer:the answer is c/ all real values of x where 1<x<4

Step-by-step explanation:

edge 2020

Answer:

D. 3.6

Step-by-step explanation:

=> Taking proportionality of the similar sides to find BC

[tex]\frac{AB}{AD}=\frac{BC}{DE}[/tex]

[tex]\frac{3}{5} = \frac{BC}{6}[/tex]

Multiplying 6 to both sides

[tex]BC = 0.6 * 6[/tex]

BC = 3.6

Answer:

A.

f is a quadratic function, which means it's graph is a parabola.

Notice that the coefficient of is negative, so the parabola opens downwards.

the x-coordinate of a parabola is always determined by the formula: 

where a is coefficient of the  term, and b is the coefficient of the x term.

Thus, x-coordinate of the vertex of the graph of f is :

the y-coordinate of the vertex is f(8)=-8*8+16*8-60=4.

The vertex is (8, 4).

This means that the maximum daily profit is when exactly 8 candles are sold.

B.

The x-intercepts are the values of x such that f(x)=0,

so to find these values we solve:

complete the square:

so x-8=2      or x-8=-2

the roots are x=10 and  x=6, are the roots.

This means that when the shop sells exactly 6 or 10 candles, it makes no profit.

Answer: d (8, 4); The vertex represents the maximum profit.

Explanation: i got it right on the test

Answer:

20

Step-by-step explanation:

Answer:

$61.20

Step-by-step explanation:

15% sale:

40% sale:

Answer:

|Z| = |-0.126| = 0.126 < 1.645

Null hypothesis is accepted

The retiring citizens is taken to investigate whether the new bill has raised the average age at which people actually retire.

μ = 57.5

Step-by-step explanation:

Explanation:-

The average retirement age for a certain country was reported to be 56.4 years

The mean of the sample x⁻ = 56.4

The standard  deviation of the Population 'σ'= 55 years

The mean of the population μ = 57.5

Null hypothesis: H₀:The retiring citizens is taken to investigate whether the new bill has raised the average age at which people actually retire.

μ = 57.5

Alternative Hypothesis : H₁: μ ≠57.5

Test statistic

         [tex]Z = \frac{x^{-}-mean }{\frac{S.D}{\sqrt{n} } }[/tex]

critical value:

[tex]Z_{\frac{\alpha }{2} } = Z_{0.05} =1.645[/tex]

[tex]Z = \frac{56.4-57.5 }{\frac{55}{\sqrt{40} } } = -0.126[/tex]

|Z| = |-0.126| = 0.126 < 1.645

The null hypothesis is accepted

Conclusion:-

The retiring citizens is taken to investigate whether the new bill has raised the average age at which people actually retire.

μ = 57.5

Answer:

Necesita cubrir 4800 cm^2.

Step-by-step explanation:

La pregunta está incompleta:

Laura quiere cubrir con papel de china una puerta como la que se muestra en el dibujo. Las medidas son 80 cm de largo y 60 cm de ancho.

Tenemos que calcular la superficie de la puerta, cuyas medidas son 80 cm de largo y 60 cm de ancho.

Para calcular el área simplemente multiplicamos las medidas de ambos lados:

[tex]A=80\,cm\cdot 60\,cm=4800\,cm^2[/tex]

Answer:

10.71

Step-by-step explanation:

The arc length is

2*3*3.14/4 = 4.71

Add to the two side lengths to get the perimeter

4.71+3+3 = 10.71

[tex]answer = 10.71 \: millimeters \\ solution \\ radius = 3 \: millimeters \\ perimeter \: of \:quarter \: circle \\ = \frac{2\pi \: r}{4} + 2r \\ = \frac{2 \times 3.14 \times 3}{4} + 2 \times 3\\ = \frac{18.84}{4} + 6 \\ = \frac{18.84 + 6 \times 4}{4} \\ = \frac{18.84 + 24}{4} \\ = \frac{42.84}{4} \\ = 10.71 \: millimeters \\ hope \: it \: helps[/tex]

Answer:

  7290

Step-by-step explanation:

Put 5 in the formula and evaluate.

  a(5) = 90·3^(5-1) = 90·81 = 7290

There will be 7290 bacteria at the beginning of hour 5.

Answer:

The advertising cost, X₄ = 5.626 million

The 80% confidence limits for X₄ is (5.041 , 6.100)

The 80% prediction limits for X₄ is (4.048 , 7.094)

Step-by-step explanation:

Using MINITAB

The regression equation is X₄ = 4.14 + 0.0431 X₁ - 0.800 X₂ + 0.00059 X₃ - 0.661 X₅ + 0.057 X₆

Predictor Coef SE Coef T P

Constant 4.142 1.626 2.55 0.019

X₁ 0.043089 0.009466 4.55 0.000

X₂ -0.7998 0.2515 -3.18 0.005

X₃ 0.000590 0.004221 0.14 0.890

X₅ -0.6606 0.1542 -4.28 0.000

X₆ 0.0574 0.1254 0.46 0.652

S = 1.07911 R-Sq = 93.4% R-Sq(adj) = 91.8%

Analysis of Variance

Source DF SS MS F P

Regression 5 345.966 69.193 59.42 0.000

Residual Error 21 24.454 1.164

Total 26 370.420

Source DF Seq SS

X₁ 1 309.464

X₂ 1 8.699

X₃ 1 5.994

X₅ 1 21.566

X₆ 1 0.244

Unusual Observation

Obs X₁ X₄ Fit SE Fit Residual St Resid

17 398 5.500 7.714 0.641 -2.214 -2.55 R

27 400 7.000 7.366 1.025 -0.336 -1.00 X

Where R is observation with a large standardized residual.

Where X is observation whose X values give it large influence.

Predicted values for new Observations

New

Obs Fit SE Fit 80% Cl 80% Pl

1 5.571 0.400 (5.041 , 6.100) (4.048 , 7.094)

Values of Predictors for New Observations

New

Obs X₁ X₂ X₃ X₅ X₆

1 163 2.40 188 6.60 10.0

∴ The advertising cost, X₄ = 5.626 million, The 80% confidence limits for X₄ is (5.041 , 6.100), and The 80% prediction limits for X₄ is (4.048 , 7.094)

Answer:

Step-by-step explanation:

Given that :

The probability of winning is 0.8

i.e P(winning) = 0.8

Then P(losing) = 0.2

a) Y ~ Geometric distribution

[tex]P = P(loose) =0.2 \\ \\ \mu_{\delta} = \dfrac{1}{P}= \dfrac{1}{0.2}\\ \\ = 5.0 \\ \\ \\ \dfrac{\sigma ^2 }{\delta } = \dfrac{1-P}{P^2} \\ \\ =\dfrac{0.8}{0.04} \\ \\ = 20[/tex]

b) Y ~ Negative Binomial Distribution

[tex]P = P (loose) =0.2 \\ \\ \delta = number \ of \ loss = 4 \\ \\ \mu_{\delta} = \dfrac{\delta}{P} \\ \\ =\dfrac{4}{0.2} \\ \\ = 20 \\ \\ \\ \sigma ^2_{\delta} = \dfrac{\delta (1-P)}{P^2} \\ \\ = \dfrac{4*0.8}{0.04}\\ \\ = 80[/tex]

c) Y ~ Binomial Distribution;

n = 100 ; P = 0.8

[tex]\mu_{\delta} = nP \\ \\ = 100*0.8 \\ \\ = 80 \\ \\ \\ \sigma_{\delta}^2 = nP(1-P) \\ \\ =80*0.2 \\ \\ = 16[/tex]

Answer:

true

is the answer

Answer:

Answer is given below.

Step-by-step explanation:

let us solve the numerator first

=4x²-14x+6

=2(2x²)+2(-7x)+2(3)

= GCF of the terms of the numerator is 2.

denominator

x³-7x²+12x

x(x²)+x(-7x)+x(12)

GCF of the terms of the denominator is x.

factorise the numerator

4x²-14x+6

4x²-2x-12x + 6  (by splitting the middle term; the numbers should produce the product  4*6 and when the no.s are added they should give -14)

(4x²-2x) + (-12x+6)

2x(2x-1) -6(2x-1)

(2x-6)(2x-1)

factors are

(2x-6), (2x-1)

denominator

this can also be done by splitting the middle term

x³-7x²+12x

x³-3x²-4x²+12x

(x³-3x²) + (-4x²+12x)

x²(x-3) -4x(x-3)

(x²-4x)(x-3)

factors are

(x²-4x), (x-3)

Answer:

1) 23/2

2) 529/25

Step-by-step explanation:

Transformation:

[tex]4\frac{1}{2} = \frac{(2*4) + 1}{2} = \frac{9}{2}[/tex]

[tex]2\frac{5}{9} = \frac{(9*2) + 5}{9} = \frac{23}{9}[/tex]

A = [tex]\frac{9}{2} * \frac{23}{9} = \frac{23}{2}[/tex]

-----------------------------

Transformation:

[tex]4\frac{3}{5} = \frac{(5*4) + 3}{5} = \frac{23}{5}[/tex]

A = [tex](\frac{23}{5})^{2} = \frac{529}{25}[/tex]

Answer:

Slope: The percent that voted falls by 0.1271 units per year.

Step-by-step explanation:

The slope of a regression line represent the average rate of change in the dependent variable (y) based upon the changes in the independent variable (x).

In this case the regression equation provided is:

y = -0.1271 x + 307.53

The slope of the line is -0.1271.

The dependent variable is the percent that voted and the independent variable is the year.

The slope of -0.1271 indicates that every year, on average, the percent that voted decreases by 0.1271 units.

Or the percent that voted falls by 0.1271 units per year.

Answer:

Step-by-step explanation:

Confidence interval for the difference between two population means is written in the form,

difference in sample means ± margin of error

The difference in sample means is the point estimate for the difference in population means. In the given scenario, the point estimate is the difference in mean amount spent by the sampled customers on a trip to Target or​ Walmart.

Since the interval was (- $15.05​,$2.95), it means that the lower limit is - $15.05 and the upper limit us $2.95.

Therefore, the 95% confidence interval is providing a range that we are 95% confident that the true difference in mean amount spent by Target customers and Walmart customers falls between - $15.05​ and $2.95

Answer:

Red apples to all apples =2/11

Red apples to green apples =2/9

Step-by-step explanation:

There are 11 total apples 9 of them are green and the rest are red so there are 11-9=2 red apples

The ratio of red apples to all apples = number of red apples ÷ total apples number = 2÷11

The ratio of red apples to green apples = number of red apples ÷ number of green apples = 2÷9

Answer:

Red apples to all apples =2/11

Red apples to green apples =2/9

Step-by-step explanation:

There are 11 total apples 9 of them are green and the rest are red so there are 11-9=2 red apples

The ratio of red apples to all apples = number of red apples ÷ total apples number = 2÷11

The ratio of red apples to green apples = number of red apples ÷ number of green apples = 2÷9

Step-by-step explanation:

Answer:

[tex]10[/tex]

Step-by-step explanation:

[tex]05[/tex]

If the units place is higher than 5, then add 1 to the tens place.

Answer:

The students should request an examination with 5 examiners.

Step-by-step explanation:

Let X denote the event that the student has an “on” day, and let Y denote the

denote the event that he passes the examination. Then,

[tex]P(Y)=P(Y|X)P(X)+P(Y|X^{c})P(X^{c})[/tex]

The events ([tex]Y|X[/tex]) follows a Binomial distribution with probability of success 0.80 and the events ([tex]Y|X^{c}[/tex]) follows a Binomial distribution with probability of success 0.40.

It is provided that the student believes that he is twice as likely to have an off day as he is to have an on day. Then,

[tex]P(X)=2\cdot P(X^{c})[/tex]

Then,

[tex]P(X)+P(X^{c})=1[/tex]

⇒

[tex]2P(X^{c})+P(X^{c})=1\\\\3P(X^{c})=1\\\\P(X^{c})=\frac{1}{3}[/tex]

Then,

[tex]P(X)=1-P(X^{c})\\=1-\frac{1}{3}\\=\frac{2}{3}[/tex]

Compute the probability that the students passes if request an examination with 3 examiners as follows:

[tex]P(Y)=P(Y|X)P(X)+P(Y|X^{c})P(X^{c})[/tex]

        [tex]=[\sum\limits^{3}_{x=2}{{3\choose x}(0.80)^{x}(1-0.80)^{3-x}}]\times\frac{2}{3}+[\sum\limits^{3}_{x=2}{{3\choose x}(0.40)^{3}(1-0.40)^{3-x}}]\times\frac{1}{3}[/tex]

       [tex]=0.715[/tex]

The probability that the students passes if request an examination with 3 examiners is 0.715.

Compute the probability that the students passes if request an examination with 5 examiners as follows:

[tex]P(Y)=P(Y|X)P(X)+P(Y|X^{c})P(X^{c})[/tex]

        [tex]=[\sum\limits^{5}_{x=3}{{5\choose x}(0.80)^{x}(1-0.80)^{5-x}}]\times\frac{2}{3}+[\sum\limits^{5}_{x=3}{{5\choose x}(0.40)^{x}(1-0.40)^{5-x}}]\times\frac{1}{3}[/tex]

       [tex]=0.734[/tex]

The probability that the students passes if request an examination with 5 examiners is 0.734.

As the probability of passing is more in case of 5 examiners, the students should request an examination with 5 examiners.

Answer:

Now we have everything in order to replace into formula (1):

[tex]18-2.262\frac{2.75}{\sqrt{10}}=16.03[/tex]    

[tex]18+2.262\frac{2.75}{\sqrt{10}}=19.97[/tex]    

Step-by-step explanation:

Information given

[tex]\bar X=18[/tex] represent the sample mean

[tex]\mu[/tex] population mean (variable of interest)

s=2.75 represent the sample standard deviation

n=10 represent the sample size  

Confidence interval

The confidence interval for the mean is given by the following formula:

[tex]\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}[/tex]   (1)

The degrees of freedom are given by:

[tex]df=n-1=10-1=9[/tex]

The Confidence is 0.90 or 90%, the significance is [tex]\alpha=0.1[/tex] and [tex]\alpha/2 =0.05[/tex], and the critical vaue would be [tex]t_{\alpha/2}=2.262[/tex]

Now we have everything in order to replace into formula (1):

[tex]18-2.262\frac{2.75}{\sqrt{10}}=16.03[/tex]    

[tex]18+2.262\frac{2.75}{\sqrt{10}}=19.97[/tex]    

Answer:

3.3

Step-by-step explanation:

18x-5x=13+20

13x=33

x=2.5

The question is incomplete, I will however explain, with an illustration, how to determine the center and radius of a circle.

Step-by-step explanation:

The standard equation of a circle is given as:

(x - a)² + (y - b)² = r² ........................(1)

Where (a, b) is the center of the circle, and r is the radius.

An expression can be given for us to find the center and the radius of the circle.

Suppose we were given the expression:

x² + y² - 10x + 4y - 7 = 0.....................(2)

To find the center and the radius, it is left for us to rewrite (2) in the form of (1).

Rearranging (2), we have

(x² - 10x) + (y² + 4y) = 7

Completing the squares of each bracket

(x² - 10x + 25 - 25) + (y² + 4y + 4 - 4) = 7

(x² - 10x + 25) + (y² + 4y + 4) - 25 - 4 = 7

(x² - 10x + 25) + (y² + 4y + 4) - 29 = 7

(x - 5)² + (y + 2)² = 7 + 29

(x - 5)² + (y + 2)² = 36

Or

(x - 5)² + (y + 2)² = 6² .....................(3)

Comparing (3) with one, we see that

a = 5, b = -2, and r = 6

Therefore it is a circle centered at (5, -2) with a 6 unit radius.