8x - 4 < - 12 or 8x + 7 >23 i need help to find answer

Answer:

Answer is A $172.25

Step-by-step explanation:

Step 1: Our output value is 575.50.

Step 2: We represent the unknown value with $x$.

Step 3: From step 1 above,$575.50=100\%$.

Step 4: Similarly, $x=30\%$.

Step 5: This results in a pair of simple equations

$575.50=100\%(1)$.

$x=30\%(2)$.

Step 6: By dividing equation 1 by equation 2 and noting that both the RHS (right hand side) of both

equations have the same unit (%); we have

$\frac{575.50}{x}=\frac{100\%}{30\%}$

Step 7: Again, the reciprocal of both sides gives

$\frac{x}{575.50}=\frac{30}{100}$

$\Rightarrow x=172.65$

Therefore, $30\%$ of $575.50$ is $172.65$

Answer:

The total that will be saved at a 30% discount is $172.65

Explanation:

Since, the marked up price of the item will be $575.50,

and the discount percentage is 30%,

Therefore, $ 172.65 will be saved.

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:

There is insufficient statistical evidence to prove that the companies stated color distribution is not correct therefore, the overall proportions of the colors are correctly stated as above

Step-by-step explanation:

We have that

H₀: 0.24 blue, 0.13 brown, 0.20 green, 0.16 orange, 0.13 red and 0.14 yellow

The Data given are as follows;

Hₐ: The stated distribution of M&M is incorrect

                        Blue   Brown   Green    Orange   Red    Yellow   Total

Observed:        105     72          89          84           70       80          500

Expected:         120     65         100         80           65       70      

We have;

[tex]\chi ^{2}=\dfrac{\left (105-120 \right )^{2}}{120}+ \dfrac{\left (72-65\right )^{2}}{65} + \dfrac{\left (89-100\right )^{2}}{100} + \dfrac{\left (84-80\right )^{2}}{80} + \dfrac{\left (70-65\right )^{2}}{65} + \dfrac{\left (80-70\right )^{2}}{70} = 5.85[/tex]

At 6 - 1 = 5 degrees of freedom we find the p-value from the chi squared table as follows

P(0.05) at 5% degrees of freedom =11.070 hence our P-value is larger than 0.05 and we fail to reject the null hypothesis, hence there is insufficient statistical evidence to prove that the companies stated color distribution is not correct.

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:

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] 0.34 \leq p \leq 0.38[/tex]

For this case we can conclude that with 98% of confidence the true proportion of Drosophila in a population would be between 0.34 and 0.38.

But that doesn't means that we have 98% of PROBABILITY that the true proportion would be between 0.34 and 0.38, because we are constructing a confidence interval with sample data and we can't analyze this using probability.

Then the best answer is:

2. False

Step-by-step explanation:

For this case we have a confidence interval for the proportion of Drosophila in a population with mutation Adh-F to be given by:

[tex] 0.34 \leq p \leq 0.38[/tex]

For this case we can conclude that with 98% of confidence the true proportion of Drosophila in a population would be between 0.34 and 0.38.

But that doesn't means that we have 98% of PROBABILITY that the true proportion would be between 0.34 and 0.38, because we are constructing a confidence interval with sample data and we can't analyze this using probability.

Then the best answer is:

2. False

Answer:

true

is the answer

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:

[tex]P(19<X<91)=P(\frac{19-\mu}{\sigma}<\frac{X-\mu}{\sigma}<\frac{91-\mu}{\sigma})=P(\frac{19-55}{12}<Z<\frac{91-55}{12})=P(-3<z<2)[/tex]

And we can find this probability with this difference and using the normal standard distribution

[tex]P(-3<z<3)=P(z<3)-P(z<-3)=0.9987 -0.00135 =0.9974[/tex]

Step-by-step explanation:

Let X the random variable that represent the amount of Jen monthly phone of a population, and for this case we know the distribution for X is given by:

[tex]X \sim N(55,12)[/tex]  

Where [tex]\mu=55[/tex] and [tex]\sigma=12[/tex]

We are interested on this probability

[tex]P(19<X<91)[/tex]

And we can use the z score formula given by:

[tex]z=\frac{x-\mu}{\sigma}[/tex]

Replacing the info we got:

[tex]P(19<X<91)=P(\frac{19-\mu}{\sigma}<\frac{X-\mu}{\sigma}<\frac{91-\mu}{\sigma})=P(\frac{19-55}{12}<Z<\frac{91-55}{12})=P(-3<z<2)[/tex]

And we can find this probability with this difference and using the normal standard distribution

[tex]P(-3<z<3)=P(z<3)-P(z<-3)=0.9987 -0.00135 =0.9974[/tex]

Answer:

  aₙ = 7 +3(n -1)

Step-by-step explanation:

The numbers in the given sequence have a common difference, so this is an arithmetic sequence. The formula for the n-th term applies.

  aₙ = a₁ +d(n -1)

The first term is 7. The common difference is 10-7 = 3. Using the above formula for the n-th term, we find it to be ...

  aₙ = 7 +3(n -1)

__

Additional comment

This can be simplified to ...

  aₙ = 3n +4

Answer:

20

Step-by-step explanation:

Answer:

$61.20

Step-by-step explanation:

15% sale:

40% sale:

Answer:

Step-by-step explanation:

Hello!

The variable of interest is "the time a fight lasts" measured in seconds

The five number summary for her first 12 UFC fights are:

Minimum: Min= 14

First Quartile: Q₁= 25

Second Quartile/Median: Me= 44

Third Quartile: Q₃= 64

Maximum: Max= 289

a)

Three of her fights lasted more than one minute: 289, 267, 66. Out of these three fights, you have to determine if they are outliers using the IQR method.

The IQR is the distance between the third quartile and the first quartile

IQR= Q₃ - Q₁= 64 - 25= 39

Remember, an outlier is an observation that is significantly distant from the rest of the data set. They usually represent experimental errors (such as a measurement) or atypical observations. Some statistical measurements, such as the sample mean, are severely affected by this type of values and their presence tends to cause misleading results on a statistical analysis.  

Considering the 1st quartile (Q₁), the 3rd quartile (Q₃) and the interquartile range IQR, any value X is considered an outlier if:

X < Q₁ - 1.5 IQR

X > Q₃ + 1.5 IQR

Or extreme outliers if:

X < Q₁ - 3 IQR

X > Q₃ + 3 IQR

The limits that define if a value is an outlier or not are:

X < 25 - 1.5*39 = -33.5

X > 64 + 1.5*39= 122.5

And for extreme outliers:

X < 25 - 3*39 = -92

X > 64 + 3*39= 181

So fights that lasted less than -33.5 or more than 122.5 seconds are to be considered outliers, and those who lasted less than -92 or more than 181 seconds are extreme outliers.

Out of the three fights, the ones that lasted 289 and 267 seconds can be considered extreme values.

b) The minimum observed value for this data set is 14 seconds, values are considered to be outliers if they are less to -33.5, so there is no low outliers on the sample.

As you can see, both values that allow you to determine if the observation is an outlier or not are negative, since the variable is "the time a fight lasts" it is impossible for it to have negative values. The lowest value of time a fight can last is "zero seconds". Although mathematically correct, these values make no sense.

c)

See attachment.

d)

The average or mean is a measurement of central tendency that shows you the value around which most of the distribution will be. It is very affected by the presence of outliers, especially extreme ones. Outliers make the mean "move" towards them, this means, that if there are small outliers, then the mean will move to the lower side of the distribution. But if the outliers are big, then the mean will move to the higher side of the distribution.

For example, let's say 5 of the fight times were:

10, 37, 49, 51, 68

For these values the mean would be:

X[bar]₀= ∑X/n= (10+37+49+51+68)/5= 215/5= 43

Now let's change one of these values for an extreme one:

Small value:

0, 37, 49, 51, 68

X[bar]₁= ∑X/n= (0+37+49+51+68)/5= 205/5= 41

⇒ As you can see, one change for a smaller value reduces the mean value X[bar]₁ < X[bar]₀

Big value:

10, 37, 49, 51, 268

X[bar]₂= ∑X/n= (10+37+49+51+268)/5= 415/5= 83

⇒ In this case, changing one of the 5 values to a bigger one moved the mean to the right: X[bar]₀ < X[bar]₂

So for the given distribution, since there are at least two high outliers, you'd expect the mean to be greater than the median.

I hope this helps!

Answer:

(1/2, 1)

2

Step-by-step explanation:

x² + y² − x − 2y − 11/4 = 0

x² − x + y² − 2y = 11/4

Complete the squares.

x² − x + 1/4 + y² − 2y + 1 = 11/4 + 1/4 + 1

(x − 1/2)² + (y − 1)² = 4

The center of the circle is (1/2, 1) and the radius of the circle is 2.

Answer:

Option  A

Step-by-step explanation:

[tex](\frac{1}2} ,1)[/tex], 2 units

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]

You can use the divergence theorem:

[tex]\vec v=z\,\vec\imath+y^2\,\vec\jmath+x^2\,\vec k[/tex]

has divergence

[tex]\mathrm{div}\vec v=\dfrac{\partial z}{\partial x}+\dfrac{\partial y^2}{\partial y}+\dfrac{\partial x^2}{\partial z}=2y[/tex]

Then the rate of flow out of the cylinder (call it R) is

[tex]\displaystyle\iint_{\partial R}\vec v\cdot\mathrm d\vec S=\iiint_R\mathrm{div}\vec v\,\mathrm dV[/tex]

(by divergence theorem)

[tex]=\displaystyle2\int_0^{2\pi}\int_0^5\int_0^1r^2\sin\theta\,\mathrm dz\,\mathrm dr\,\mathrm d\theta[/tex]

(after converting to cylindrical coordinates)

whose value is 0.

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:

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:

  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: Choice B. 54degrees

Step-by-step explanation:

Angles 1 4 5 8 are equal and angles 2 3 6 7 are also equal. These two sets of angles of supplementary(you‘d get 180 by adding them).

so

13x+9=180-(5x+9)

by simplifying the equation youll get

18x+18=180

x=9

so angle 7(and therefore angle 6) equals

5*9+9=54

Answer:

SA = 1,176 ft².

Step-by-step explanation:

To find the surface area of the triangular prism, we can solve for the rectangular base, both triangular faces, and lateral sides separately.

For the rectangular base: (Use formula l×w)

20 × 18 = 360 ft²

For the triangular faces: (Use formula 1/2(b·h)

1/2(18 × 12) = 108 ft²

Since there are two faces, we need to double the amount.

108 × 2 = 216 ft².

Finally, solve for the lateral sides:

20 × 15 = 300 ft².

There are two sides, so:

300 × 2 = 600 ft².

Add up all of these areas:

600 + 216 + 360 = 1,176 ft²

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:

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:

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:

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:

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:

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

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.

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:

Step-by-step explanation:

A. x² = –100

This equation has no solution because x² is always positive.

B. 5x² = 1

then x² = 1/5

then x = 1/(√5) or x = -1/(√5)

C. 6x² + 17 = 11

then 6x² = 11 - 17 = -6

then x² = -6/6 = -1  

This equation has no solution because x² is always positive.

D. 7(x + 6) = 42

then x + 6 = 42/7 = 6

then x = 6 - 6 = 0

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:)