Answer:
x=2
Step-by-step explanation:
f(x) = -3x + 5.
f(x) =-1
-1 = -3x+5
Subtract 5 from each side
-1 -5 = -3x+5-5
-6 = -3x
Divide each side by -3
-6/-3 = -3x/-3
2 =x
How would I solve this problem. A researcher wishes to estimate the mean height of women aged between 60 and 65 in the U.S. She desires a margin of error of 0.3 inches. Past studies suggest that a population standard deviation of 3.3 inches is reasonable. Estimate the minimum sample size needed to estimate the population mean with the stated accuracy.
Answer:
465
Step-by-step explanation:
Margin of error = critical value × standard error
ME = CV × SE
Assuming 95% confidence, CV = z = 1.96.
Standard error is:
SE = σ / √n
SE = 3.3 / √n
Given margin of error of 0.3:
0.3 = 1.96 × 3.3 / √n
n = 465
laura quiere cúbrir con papel de china una puerta como la que se muestran el dibujo cuánto centímetros cuadrados es la que tendra que cubrir con papel de china
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]
The function f(x) = −x2 + 16x − 60 models the daily profit, in dollars, a shop makes for selling candles, where x is the number of candles sold. Determine the vertex, and explain what it means in the context of the problem. (6, 10); The vertex represents the maximum profit. (6, 10); The vertex represents the minimum profit. (8, 4); The vertex represents the minimum profit. (8, 4); The vertex represents the maximum profit.
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
How much money does the average professional hockey fan spend on food at a single hockey game? That question was posed to 10 randomly selected hockey fans. The sampled results show that sample mean and standard deviation were $ 18.00 and $ 2.75, respectively. Use this information to create a 90% confidence interval for the mean. Express the answer in the form x overbar plus or minus t Subscript alpha divided by 2 Baseline (s divided by StartRoot n EndRoot ).
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]
The average retirement age for a certain country was reported to be 56.4 years according to an international group dedicated to promoting trade and economic growth. With the pension system operating with a deficit, a bill was introduced by the government during the summer to raise the minimum retirement age from 60 to 62. Suppose a survey of 40 retiring citizens is taken to investigate whether the new bill has raised the average age at which people actually retire. Assume the standard deviation of the retirement age is 55 years. Using α=0.10
Required:
Calculate the probability of a Type II error occurring if the actual population age is 57.5 years old.
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
A fluid has density 860 kg/m3 and flows with velocity v = z i + y2 j + x2 k, where x, y, and z are measured in meters and the components of v in meters per second. Find the rate of flow outward through the cylinder x2 + y2 = 25, 0 ≤ z ≤ 1.
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.
A box contains 16 transistors, 4 of which are defective. if 4 are selected at random, find the probability that
a. all are defective.
b. none are defective.
Answer:
(a)0.0005
(b)0.2720
Step-by-step explanation:
Total Number of Transistors = 16
To find the probability that 4 selected at random are defective (or non-defective), we find the probability of the 1st, 2nd, 3rd, and 4th defective (or non-defective) items in that order, Note that the selection is without replacement.
(a)Probability that all are defective
Number of Defective Transistors =4
P(all are defective) [tex]=\dfrac{4}{16} \times \dfrac{3}{15} \times \dfrac{2}{14} \times \dfrac{1}{13}[/tex]
=0.0005
(b)Probability that none are defective
Number of Non-Defective Transistors =16-4=12
P(none are defective) [tex]=\dfrac{12}{16} \times \dfrac{11}{15} \times \dfrac{10}{14} \times \dfrac{9}{13}[/tex]
=0.2720
Mars, Inc. candy company claims the overall proportions for the colors of M&M’s are: .24 blue, .13 brown, .20 green, .16 orange, .13 red, and .14 yellow. You buy a large bag of M&M’s and observe the following counts: 105 blue, 72 brown, 89 green, 84 orange, 70 red, 80 yellow. At the 0.05 level of significance, is there evidence that the overall proportions for the colors are as stated above?
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.
Determine the center and radius of the circle described by the question.
(X+2)
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.
Question 2 of 10
2 Points
What is the sum of the rational expressions below?
2x+3/3x+x/x+1
Answer:
5x^2+5x+3/3x^2+3x
Step-by-step explanation:
Please answer this correctly
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
En una encuesta sobre preferencias entre los deportes Tenis (T), Surf (S) y Golf (G) se sabe que:
90 personas fueron encuestadas
15 personas prefieren Golf
10 no prefieren ninguno de estos deportes
ninguno de los que prefiere los deportes Tenis ó Surf prefieren Golf
30 prefieren sólo Surf
20 prefieren sólo Tenis
a) ¿Cuántas personas prefieren dos de estos deportes?
b) ¿Cuántos prefieren sólo uno de estos deportes?
Answer:
a) 15
b) 65
Step-by-step explanation:
Adjunto se encuentra el diagrama asociado a esta situación. Comenzamos por ubicar aquellas afirmaciones que relacionan todos los deportes. Sabemos que 10 personas no prefieren ningún deporte. Luego, ubicamos 10 fuera de los conjuntos mostrados. Sabemos que 30 personas prefieren sólo surf y 20 personas prefieren sólo Tenis. Es decir, hay 30 personas en el conjunto S que no intersectan a los otros dos. En este momento, hemos ubicado a 60 personas. Nos hacen falta 30 personas. La afirmación "15 personas prefieren Golf" significa que la suma de los números dentro del conjunto G es 15. La afirmación "ninguno de los que prefieren los deportes Tenis o Surf prefieren el golf. Es decir, que la intersección de G con T y con S son vacías. Es decir que las 15 personas que prefieren golf, lo prefieren únicamente. Esto nos deja con 15 personas por ubicar. El único lugar donde podemos ubicar a dichas 15 personas es en en la intersección de T y S.
a). ¿cuántas personas prefieren dos de estos deportes? Por el diagrama, son aquellas personas que prefieren Tenis o Surf. Es decir, 15.
b) ¿Cuánto prefieren sólo uno de estos deportes? Es la suma de aquellos que prefieren sólo un deporte. Es decir, sólo G, sólo T o sólo S. Es decir 15+20+30 = 65.
The amount of Jen’s monthly phone bill is normally
distributed with a mean of $55 and a standard deviation of $12. What percentage of her phone bills are between $19 and $91?
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]
Suppose an All Greens store in Sonoma, California, wants to estimate a range of advertising costs appropriate to its store. If it spends too little on advertising, it will not reach enough customers. However, it does not want to overspend on advertising for this type and size of store. At this store, x1 = 163, x2 = 2.4, x3 = 188, x5 = 6.6, and x6 = 10. Use these data to predict x4 (advertising costs) and find an 80% confidence interval for your prediction. (Use 2 decimal places.)
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)
Sam colors each tile in a 4 by 4 grid white or black. A coloring is called rotationally
symmetric if the grid can be rotated 90, 180, or 270 degrees to achieve the same pattern.
Two colorings are called rotationally distinct if neither can be rotated to match the
other. How many rotationally distinct ways are there for Sam to color the grid such
that the colorings are not rotationally symmetric?
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
You are renting a car that charges a $30 fee plus 40 cents a mile. The rate of change
is $30.
True
False
Answer:
true
is the answer
Please answer this correctly
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]
A student is getting ready to take an important oral examination and is concerned about the possibility of having an "on" day or an "off" day. He figures that if he has an on day, then each of his examiners will pass him, independently of one another, with probability 0.8, whereas if he has an off day, this probability will be reduced to 0.4. Suppose that the student will pass the examination if a majority of the examiners pass him. If the student believes that he is twice as likely to have an off day as he is to have an on day, should he request an examination with 3 examiners or with 5 examiners?
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.
You are playing a game called cornhole and let’s assume that you are reallygood at it with the winning probability is 0.8. For the following parts, find (a) the name ofthe appropriate probability distribution and correct parameters, (b) the expected value and (c) the variance of Y.
A. Y = the number of games it takes you to lose one time.
B. Y = the number of games it takes you to lose four times.
C. Y the number of times you win out of 100 games.
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]
winnie and kevin like to create their own triathlon courses to challenge each other. last weekend, winnie created a course that included a swim of 3/4 of a mile, a bike ride of 57/4 miles and a run of 13/4 miles. how long was the course winnie created?
Many traffic experts argue that the most important factor in accidents is not the average speed of cars but the amount of variation. Suppose that the speeds of a sample of 200 cars were taken over a stretch of highway that has seen numerous accidents. Compute the standard deviation of the speeds in Excel file Q-14.xlsx.
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.
How much will you save If you buy an Item listed at $575.50 at a 30 percent discount?
OA. $172.65
OB.
$176.25
O C. $185.63
Reset
Next
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.
There are 11 apples in a basket. 9 of these apples are green. The rest of them are red. What is the ratio of red apples to all apples in the basket? What is the ratio of red apples to green apples?
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:
Perhaps the most popular fighter since the turn of the decade, Ronda Rousey is famous for defeating her opponents quickly. The five number summary for the times of her first 12 UFC (Ultimate Fighting Championship) fights, in seconds, is .(a) Only three of her fights have lasted more than a minute, at 289, 267, and 66 seconds, respectively. Use the IQR method to see which, if any, of these values are high outliers. (b) Are there any low outliers in these data, according to the IQR method? (c) Draw the boxplot for Ronda Rousey's fight times. (d) Based on the boxplot or five number summary, would we expect Ronda's mean fight time to be greater than or less than her median?
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!
4x2 - 14x + 6
x3 - 7x2 + 12x
What is the GCF of the terms in the numerator and denominator? Rewrite the expression by factoring out any common
factors.
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)
Determine the least number of patties that will share equally among groups og 6, 9, 12
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.
What is the measure of <6?
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
Can someone plz help me solved this problem I need help ASAP plz help me! Will mark you as brainiest!
Answer:
2 is the answer
Step-by-step explanation:
area=1/2*base*height
as height = 2*base and area =4 it comes
1/2*2*base*base=4
so base *base=4
so base = 2
A researcher reports a 98% confidence interval for the proportion of Drosophila in a population with mutation Adh-F to be [0.34, 0.38). Therefore, there is an approximate probability of 0.98 that the proportion of Drosophola with this mutation is between 0.34 and 0.38.1. True 2. False
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
State if each scenario involves a permutation or a combination. Then find the number of possibilities.
The batting order for seven players on a 8 person team.
a)Permutations: 120.960
b)Combinations: 20,160
c)Permutations: 40320
d)Combinations: 8
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