Answer:
B. One of the populations is normally distributed.
Step-by-step explanation:
To test a claim about two population standard deviation or variance, it is imperative that the data meets certain requirements which include :
Randomness : Data must not be biased as such it must be drawn as a random sample from a larger group.
The data must be independent. That is not related to one another, the outcome of one should not rely on the outcome or value of another.
Both groups must be drawn From a population which is normally distributed.
One group being normally distributed by stribuyed while the other isn't a requirement for hypothesis testing in this scenario.
Put the following equation of a line into slope-intercept form, simplifying all
fractions.
12x - 3y = 15
Help pls
Answer:
Pretty sure its y=4x-5 hope it helped
Step-by-step explanation:
The height and weight of several adults were recorded:
Using this model, what would be the weight of someone who is 5.8 ft tall? Round your answer to the nearest tenth. You must find the quadratic regression equation first.
Weight of someone who is 5.8ft tall is 149.8 lbs.
What is a quadratic equation?A quadratic equation is a method of representation of a unknown variable by some variable of degree upto 2.
How to find the weight?a=5.607,b=-12.009,c=30.648
Let, y= weight(lbs) and x=height(ft)
y=5.61*x*x-12x+30.65
y=5.61*5.8*5.8-12*5.8+30.65
y=149.77
y≈149.8lbs.
Weight of someone having height 5.8ft tall is 149.8lbs.
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PLEASE HELP ASAP!!!!
What is the square of 22?
A.44
B.444
C.844
D.484
If the product of a and cis negative, you subtract the factors of the product to arrive at c. True False
9514 1404 393
Answer:
false
Step-by-step explanation:
The statement is nonsense (false). Regardless of the sign of a product, subtraction plays no part in anything related to it.
What is the largest value of x for which the following equation has a real solution (x,y)?
Answer:
x = 9/2
Step-by-step explanation:
x^2+7x+y^2+4y=191/4
Complete the square: (x+7/2)^2-(49/4)+(y+2)^2-4 = 191/4
Simplify: (x+7/2)^2+(y+2)^2=191/4+49/4+4
(x+7/2)^2 + (y+2)^2 = 64
(x+7/2)^2 + (y+2)^2 = (8)^2
Center of circle -> (-7/2, -2)
Radius -> 8
-7/2 + 8 = 9/2
x = 9/2
51.Tandin Dorji was married to five women. First woman had three
daughters and five sons and the youngest wife had two sons. Two
of the remaining wives had one son each. If the ratio of children of
5th wife was 1:3 with the children of other wives. How many
children does Tandin have
Answer:
Tandin has 16 children.
Step-by-step explanation:
Total of children:
3+5 = 8(first woman)
2(youngest wife)
1 + 1 = 2(two of the remaining wives)
So
8 + 2 + 2 = 12
If the ratio of children of 5th wife was 1:3 with the children of other wives.
Thus the 5th wife has 12/3 = 4 children.
How many children does Tandin have?
12 + 4 = 16
Tandin has 16 children.
What is the volume of this prism?
112 cubic units
28 cubic units
56 cubic units
16 cubic units
Answer:
the answer is 56 cubic units
Use the following graph to evaluate f’(-5) and f’(-1).
Answer:
Bonsoir,
f'(-5)=-4/3
f'(-1) =3/4
Step-by-step explanation:
f'(-5) = ?
2 points : (-6,9) and (-3,5)
f'(-5)=(9-5)/(-6-(-3))=-4/3
f'(-1) = ?
2 points : (-3,5) and (1,8)
f'(-1)=(5-8)/(-3-1)=3/4
The lines are perpendicular
The derivative at the points -5 and -1 are:
f’(-5) = -4/3
f’(-1) = 3/4
What is derivative at a point on line?The slope of the tangent line to the graph of a function at a point is called the derivative of the function at that point.
We consider the line on which where the x coordinate -5 lies.
It is the line with points (-3, 5) and (-6, 9).
Slope of the line = [tex]\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex] = [tex]\frac{9-5}{-6+3} = \frac{-4}{3}[/tex]
f'(-5) = -4/3
We consider the line on which where the x coordinate -1 lies.
It is the line with points (-3, 5) and (1, 8).
Slope of the line = [tex]\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex] = [tex]\frac{8-5}{1+3} = \frac{3}{4}[/tex]
f'(-1) = 3/4
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I NEED HELP PLEASE!!!!
Answer:
the answer to that's is B bud
An automobile manufacturer has given its jeep a 51.3 miles/gallon (MPG) rating. An independent testing firm has been contracted to test the actual MPG for this jeep since it is believed that the jeep has an incorrect manufacturer's MPG rating. After testing 230 jeeps, they found a mean MPG of 51.1. Assume the population variance is known to be 6.25. A level of significance of 0.02 will be used. Make the decision to reject or fail to reject the null hypothesis.
Answer:
The p-value of the test is 0.2262 > 0.02, which means that the decision is to fail to reject the null hypothesis.
Step-by-step explanation:
An automobile manufacturer has given its jeep a 51.3 miles/gallon (MPG) rating.
At the null hypothesis, we test if the mean is of 51.3, that is:
[tex]H_0: \mu = 51.3[/tex]
An independent testing firm has been contracted to test the actual MPG for this jeep since it is believed that the jeep has an incorrect manufacturer's MPG rating.
This means that at the alternative hypothesis, we test if the mean is different of 51.3, that is:
[tex]H_0: \mu \neq 51.3[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
51.3 is tested at the null hypothesis:
This means that [tex]\mu = 51.3[/tex]
After testing 230 jeeps, they found a mean MPG of 51.1. Assume the population variance is known to be 6.25.
This means that [tex]n = 230, X = 51.1, \sigma = \sqrt{6.25} = 2.5[/tex]
Value of the test statistic:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{51.1 - 51.3}{\frac{2.5}{\sqrt{230}}}[/tex]
[tex]z = -1.21[/tex]
P-value of the test and decision:
The p-value of the test is the probability of the sample mean differing from 51.1 by at least 0.2, which is P(|z| > 1.21), which is 2 multiplied by the p-value of z = -1.21.
Looking at the z-table, z = -1.21 has a p-value of 0.1131.
2*0.1131 = 0.2262
The p-value of the test is 0.2262 > 0.02, which means that the decision is to fail to reject the null hypothesis.
Given that f(x) = logo x, write a function that translates f(x) down 4 units and then
reflects it across the x axis.
Answer:
Answer 2/B
Step-by-step explanation:
The one with Parentheses
-(log6 x-4)
If an object of mass m is dropped from rest, one model for its speed v after t seconds, taking air resistance into account is: c= mg/c (1- e^ -ct/m), where g is the acceleration due to gravity and c is a positive constant describing air resistance.
Required:
a. Calculate lim v
t→[infinity]
b. What is the meaning of this limit? (choose from the following options)
1. It is the time it takes the object to reach its maximum speed.
2. It is the speed the object reaches before it starts to slow down.
3. It is the time it takes the object to stop.
4. It is the speed the object approaches as time goes on.
Answer:
a. mg/c b. 4. It is the speed the object approaches as time goes on.
Step-by-step explanation:
a. Calculate lim v as t→[infinity]
Since v = mg/c(1 - e^ -ct/m)
[tex]\lim_{t \to \infty} v = \lim_{t \to \infty} (\frac{mg}{c}[1 - e^{-\frac{ct}{m} } ] )[/tex]
[tex]\lim_{t \to \infty} v =[/tex] mg/c(1 - e^(-c(∞)/m))
[tex]\lim_{t \to \infty} v =[/tex] mg/c(1 - e^(-∞/m))
[tex]\lim_{t \to \infty} v =[/tex] mg/c(1 - e^(-∞))
[tex]\lim_{t \to \infty} v =[/tex] mg/c(1 - 0)
[tex]\lim_{t \to \infty} v =[/tex] mg/c(1)
[tex]\lim_{t \to \infty} v =[/tex] mg/c
b. What is the meaning of this limit?
4. It is the speed the object approaches as time goes on.
This is because, since t → ∞ implies a long time after t = 0, the limit of v as t → ∞ implies the speed of the object after a long time. So, the limit of v as t → ∞ is the speed the object approaches as time goes on.
16 is what percent of 4
Answer:
400%
Step-by-step explanation:
Is means equals and of means multiply
16 = P *4
Divide each side by 4
16/4 = P4/4
4 = P
Change to a percent by multiply by 100 and adding the percent sign
400% = P
Let U be the event that a randomly chosen employee of an insurance company has been an underwriter. Let C be the event that a randomly chosen employee of an insurance company has been a claims adjuster. Identify the answer which expresses the following with correct notation: Of all the employees of an insurance company who have been underwriters, the probability that a randomly chosen employee of an insurance company has been a claims adjuster. Select the correct answer below:
a. P(C) AND P(U)
b. P(C|U)
c. P(U|C)
d. P(U AND C)
Answer:
b. P(C|U)
Step-by-step explanation:
Conditional Probability
We use the conditional probability formula to solve this question. It is
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]
In which
P(B|A) is the probability of event B happening, given that A happened.
[tex]P(A \cap B)[/tex] is the probability of both A and B happening.
P(A) is the probability of A happening.
In this question:
Event U: Event that a randomly chosen employee of an insurance company has been an underwriter.
Event C: Event that a randomly chosen employee of an insurance company has been a claims adjuster.
Select the correct answer below:
Claims adjuster given that it has been an underwriter, so P(C|U), and the correct answer is given by option b.
At a time hours after taking a tablet, the rate at which a drug is being eliminated r(t)= 50 (e^-01t - e^-0.20t)is mg/hr. Assuming that all the drug is eventually eliminated, calculate the original dose.
Answer:
2500 mg
Step-by-step explanation:
Since r(t) is the rate at which the drug is being eliminated, we integrate r(t) with t from 0 to ∞ to find the original dose of drug, m. Since all of the drug will be eliminated at time t = ∞.
Since r(t) = 50 (e^-01t - e^-0.20t)
m = ∫₀⁰⁰50 (e^-01t - e^-0.20t)
= 50∫₀⁰⁰(e^-01t - e^-0.20t)
= 50[∫₀⁰⁰e^-01t - ∫₀⁰⁰e^-0.20t]
= 50([e^-01t/-0.01]₀⁰⁰ - [e^-0.20t/-0.02]₀⁰⁰)
= 50(1/-0.01[e^-01(∞) - e^-01(0)] - {1/-0.02[e^-0.02(∞) - e^-0.02(0)]})
= 50(1/-0.01[e^-(∞) - e^-(0)] - {1/-0.02[e^-(∞) - e^-(0)]})
= 50(1/-0.01[0 - 1] - {1/-0.02[0 - 1]})
= 50(1/-0.01[- 1] - {1/-0.02[- 1]})
= 50(1/0.01 - 1/0.02)
= 50(100 - 50)
= 50(50)
= 2500 mg
if a,b,c,d,e are in continued proportion then a/c is equal to what ?
Answer:
huh
Step-by-step explanation:
that don't make no sense
If a,b,c,d,e are in continued proportion then a/c = a²/b²
What is Ratio?Ratio is defined as a relationship between two quantities, it is expressed one divided by the other.
It is given that
a,b,c,d,e are in continued proportion
We can write it as
a/b = b/c = c/d = d/e = k
d=ek, c=ek², b=ek³ and a=ek⁴
Here a/c
Substitute the values of a and c
⇒ ek⁴/ek²
⇒ k² [ k = a/b ]
⇒ a²/b²
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Write the point-slope form of an equation of the line through the points (-4, 7) and (5,-3).
0
A. Y+4= -1; (1 – 7)
B.Y-5 = = 10 (x+3)
OC. y +3 = = 10 (2+5)
D. y - 7= -5° (x+4)
Answer:
Step-by-step explanation:
There are two possible equations, but neither matches the the choices you listed. The choices seem to have several typographical errors.
Point-slope form of an equation of the line through the points (-4, 7) and (5,-3) is y - 7 =(-10/9)(x + 4).
How to estimate the point-slope form of an equation of the line through the points (-4, 7) and (5,-3)?Slope
[tex]$= \frac{y_{2} -y_{1}}{x_{2} -x_{1}}[/tex]
= (-3 - 7) / (5 - (-4))
= -10/9
The point-slope equation for the line of slope -(10/9) that passes through the point (5, -3).
y + 3 = (-10/9)(x - 5)
Point slope equation for the line of slope -(10/9) that passes through the point (-4, 7)
Point-slope form of an equation of the line through the points (-4, 7) and (5,-3) is y - 7 = (-10/9)(x + 4).
Therefore, the correct answer is y - 7 = (-10/9)(x + 4).
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The maximum and minimum Values of a quadratic function are called as______of the function.
Answer:
the answer is B ...Extreme Values
Cost of Building a Home According to the National Association of Home Builders, the average cost of building a home in the Northeast is per square foot. A random sample of new homes indicated that the mean cost was and the population standard deviation was . Can it be concluded that the mean cost differs from , using the level of significance
Answer:
There isn't sufficient evidence that support the claim that mean cost differs from $117.91
Step-by-step explanation:
Given that :
Population Mean cost, μ = 117.91
Sample size, n = 36
Sample mean, xbar = 122.57
Sample standard deviation, s = 20
The hypothesis :
H0 : μ = 117.91
H0 : μ ≠ 117.91
Using the one sample t test :
Test statistic
(xbar - μ) ÷ s/sqrt(n)
T = (122.57 - 117.91) ÷ 20/sqrt(36)
T = 4.66 / 3.333
T = 1.398
Decision region :
Reject H0 ; If Pvalue < α
α = 0.10
Degree of freedom, df = n - 1 = 36 - 1 = 35
Pvalue(1.398, 35) = 0.1709
Since 0.1709 > 0.10 ; WE fail to reject H0 ; therefore there isn't sufficient evidence that support the claim that mean cost differs from $117.91
4) The measure of the linear density at a point of a rod varies directly as the third power of the measure of the distance of the point from one end. The length of the rod is 4 ft and the linear density is 2 slugs/ft at the center, find the total mass of the given rod and the center of the mass
Answer:
a. 16 slug b. 3.2 ft
Step-by-step explanation:
a. Total mass of the rod
Since the linear density at a point of the rod,λ varies directly as the third power of the measure of the distance of the point form the end, x
So, λ ∝ x³
λ = kx³
Since the linear density λ = 2 slug/ft at then center when x = L/2 where L is the length of the rod,
k = λ/x³ = λ/(L/2)³ = 8λ/L³
substituting the values of the variables into the equation, we have
k = 8λ/L³
k = 8 × 2/4³
k = 16/64
k = 1/4
So, λ = kx³ = x³/4
The mass of a small length element of the rod dx is dm = λdx
So, to find the total mass of the rod M = ∫dm = ∫λdx we integrate from x = 0 to x = L = 4 ft
M = ∫₀⁴dm
= ∫₀⁴λdx
= ∫₀⁴(x³/4)dx
= (1/4)∫₀⁴x³dx
= (1/4)[x⁴/4]₀⁴
= (1/16)[4⁴ - 0⁴]
= (256 - 0)/16
= 256/16
= 16 slug
b. The center of mass of the rod
Let x be the distance of the small mass element dm = λdx from the end of the rod. The moment of this mass element about the end of the rod is xdm = λxdx = (x³/4)xdx = (x⁴/4)dx.
We integrate this through the length of the rod. That is from x = 0 to x = L = 4 ft
The center of mass of the rod x' = ∫₀⁴(x⁴/4)dx/M where M = mass of rod
= (1/4)∫₀⁴x⁴dx/M
= (1/4)[x⁵/5]₀⁴/M
= (1/20)[x⁵]₀⁴/M
= (1/20)[4⁵ - 0⁵]/M
= (1/20)[1024 - 0]/M
= (1/20)[1024]/M
Since M = 16, we have
x' = (1/20)[1024]/16
x' = 64/20
x' = 3.2 ft
what should be added to 7777 to get 4999
What is the simplified form of the following expression? Assume x > 0.
3
2x
16x
2x
4/24x²
2x
4/2443
16x4
124²
Answer:
fourth root of 24 x cubed/16x to the power four
Social media is popular around the world. Statista provides estimate of the number of social media users in various countries in as well as the projections for . Assume that the results for surveys in the United Kingdom, China, Russia, and the United States are as follows.
Use Social Media United Kingdom China Russia United States
Yes 480 215 343 640
No 320 285 357 360
Required:
a. Conduct a hypothesis test to determine whether the proportion of adults using social media is equal for all four countries. What is the p-value? Using a .05 level of significance, what is your conclusion?
b. What are the sample proportions for each of the four countries? Which country has the largest proportion of adults using social media?
c. Using a 0.05 level of significance, conduct multiple pairwise comparison tests among the four countries. What is your conclusion?
Answer:
Kindly check explanation
Step-by-step explanation:
The data table :
Use of SM _UK _China _ Russia _US _ col total
Yes ______480 __215 ___343 __640 _ 1678
No _______320 _ 285 ___357__ 360 _ 1322
Row Total__ 800 _500 __ 700_ 1000_ 3000
H0 : p1 = p2 = p3 = p4
H1 : p1 ≠ p2 ≠ p3 ≠ p4
Test statistic :
χ² = Σ(observed - Expected)² / Expected
Expected value of each cell = (Row total * column total) / N
N = grand total
Expected Values:
447.467 _279.667 _ 391.533 _ 559.333
352.533 _ 220.333 _ 308.467 _ 440.667
χ²=(2.36536+14.9527+6.01605+11.6337+3.00232 18.9793+7.63611+14.7665) = 79.352
Degree of freedom, df = (row-1)*(column-1) = (2 - 1) * (4 - 1) = 1 * 3 = 3
Using the Pvalue from Chisquare calculator :
Pvalue(79.352, 3) = 0.00000000001
Decision region :
Reject H0 ; If Pvalue < α
α = 0.05
Since 0.000000001 < 0.05 ; Reject H0 and conclude that not all population proportion are equal.
Sample proportion :
Phat = number of yes, x / total
For UK, Phat = 480/800 = 0.6
For China , Phat = 215/500 = 0.43
For Russia , Phat = 343/700 = 0.49
For US, Phat = 640/1000 = 0.64
Police sometimes measure shoe prints at crime scenes so that they can learn something about criminals. Listed below are shoe print lengths, foot lengths, and heights of males. Construct a scatterplot, find the value of the linear correlation coefficient r, and find the P-value of r. Determine whether there is sufficient evidence to support a claim of linear correlation between the two variables. Based on these results, does it appear that police can use a shoe print length to estimate the height of a male? Use a significance level of α=0.01
It does not appear that police can use a shoe print length to estimate the height of a male.
The given parameters are:
[tex]\begin{array}{cccccc}{Shoe\ Print} & {28.6} & {29.4} & {32.2} & {32.4} & {27.3} \ \\ Height (cm) & {172.5} & {176.7} & {188.4} & {170.1} & {179.2} \ \end{array}[/tex]
Rewrite as:
[tex]\begin{array}{cccccc}{x} & {28.6} & {29.4} & {32.2} & {32.4} & {27.3} \ \\ y & {172.5} & {176.7} & {188.4} & {170.1} & {179.2} \ \end{array}[/tex]
See attachment for scatter plot
To determine the correlation coefficient, we extend the table as follows:
[tex]\begin{array}{cccccc}{x} & {28.6} & {29.4} & {32.2} & {32.4} & {27.3} & y & {172.5} & {176.7} & {188.4} & {170.1} & {179.2} & x^2 & {817.96} & {864.36} & {1036.84} & {1049.76} & {745.29} & y^2 & {29756.25} & {31222.89} & {35494.56} & {28934.01} & {32112.64} & x \times y & {4933.5} & {5194.98} & {6066.48} & {5511.24} & {4892.16} \ \end{array}[/tex]
The correlation coefficient (r) is:
[tex]r = \frac{\sum(x - \bar x)(y - \bar y)}{\sqrt{SS_x * SS_y}}[/tex]
We have:
[tex]n =5[/tex]
[tex]\sum xy =4933.5+5194.98+6066.48+5511.24+4892.16 =26598.36[/tex]
[tex]\sum x =28.6+29.4+32.2+32.4+27.3=149.9[/tex]
[tex]\sum y =172.5+176.7+188.4+170.1+179.2=886.9[/tex]
[tex]\sum x^2 =817.96+864.36+1036.84+1049.76+745.29=4514.21[/tex]
[tex]\sum y^2 =29756.25+31222.89+35494.56+28934.01+32112.64=157520.35[/tex]
Calculate mean of x and y
[tex]\bar x = \frac{\sum x}{n} = \frac{149.9}{5} = 29.98[/tex]
[tex]\bar y = \frac{\sum y}{n} = \frac{886.9}{5} = 177.38[/tex]
Calculate SSx and SSy
[tex]SS_x = \sum (x - \bar x)^2 =(28.6-29.98)^2 + (29.4-29.98)^2 + (32.2-29.98)^2 + (32.4-29.98)^2 + (27.3-29.98)^2 =20.208[/tex]
[tex]SS_y = \sum (y - \bar x)^2 =(172.5-177.38)^2 + (176.7-177.38)^2 + (188.4-177.38)^2 + (170.1-177.38)^2 + (179.2-177.38)^2 =202.028[/tex]
Calculate [tex]\sum(x - \bar x)(y - \bar y)[/tex]
[tex]\sum(x - \bar x)(y - \bar y) = (28.6-29.98)*(172.5-177.38) + (29.4-29.98)*(176.7-177.38) + (32.2-29.98)*(188.4-177.38) + (32.4-29.98)*(170.1-177.38) + (27.3-29.98) *(179.2-177.38) =9.098[/tex]
So:
[tex]r = \frac{\sum(x - \bar x)(y - \bar y)}{\sqrt{SS_x * SS_y}}[/tex]
[tex]r = \frac{9.098}{\sqrt{20.208 * 202.028}}[/tex]
[tex]r = \frac{9.098}{\sqrt{4082.581824}}[/tex]
[tex]r = \frac{9.098}{63.90}[/tex]
[tex]r = 0.142[/tex]
Calculate test statistic:
[tex]t = \frac{r}{\sqrt{\frac{1 - r^2}{n-2}}}[/tex]
[tex]t = \frac{0.142}{\sqrt{\frac{1 - 0.142^2}{5-2}}}[/tex]
[tex]t = \frac{0.142}{\sqrt{\frac{0.979836}{3}}}[/tex]
[tex]t = \frac{0.142}{\sqrt{0.326612}}[/tex]
[tex]t = \frac{0.142}{0.5715}[/tex]
[tex]t = 0.248[/tex]
Calculate the degrees of freedom
[tex]df = n - 2 = 5 - 2 = 3[/tex]
The [tex]t_{\alpha/2}[/tex] value at:
[tex]df =3[/tex]
[tex]t = 0.248[/tex]
[tex]\alpha = 0.01[/tex]
The value is:
[tex]t_{0.01/2} = \±5.841[/tex]
This means that we reject the null hypothesis if the t value is not between -5.841 and 5.841
We calculate the t value as:
[tex]t = 0.248[/tex]
[tex]-5.841 < 0.248 < 5.841[/tex]
Hence, we do not reject the null hypothesis because they do not appear to have any correlation.
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What are the values of a, b, and c in the quadratic equation 0 = one-halfx2 – 3x – 2?
a = one-half, b = 3, c = 2
a = one-half, b = –3, c = –2
a = one-half, b = 3, c = –2
a = one-half, b = –3, c = 2
Answer:
b
Step-by-step explanation:
ax^2+bx+c=0
1/2x^2-3x-2=0
Answer:
B
Step-by-step explanation:
A fisheries biologist has been studying horseshoe crabs. She has sampled 100 horseshoe crabs and recorded their weight (in kilograms) and width (in centimeters). The proposed regression equation is
where the deviations ε i are assumed to be independent and Normally distributed with mean 0 and standard deviation σ . This model was fit to the data using the method of least squares. The following results were obtained from statistical software:
R 2 =0.423, s=2.2018
The quantity s = 2.2018 is an estimate of the standard deviation, σ, of the deviations in the simple linear regression model. The degrees of freedom for s are
a.) 100
b.) 99
c.) 98
d.) 2
Answer:
C. 98
Step-by-step explanation:
The proposed regression equation is weight = b + width * m
R2 = 0.423
A.) What is the regression equation for this example?
The estimate for the y-intercepts is b= 2.3013 and the estimate for the slope is m= 0.7963
In general, we can symbolize the estimated regression equation as ^Y= b + m*Xi. For this example you have to replace it with the calculated values of the regression coefficients to obtain the estimated regression equation:
^Y= 2.3013 + 0.7963Xi
B.) What is the explanatory, or predictor, variable in this study?
The explanatory or predictor variable is the variable that is suspected to have an effect over the response variable. In this example the predictor variable is:
X: Width of a horseshoe crab (cm)
C.) If the researcher wanted to test whether there is a statistically significant relationship between these two variables, what would the test statistic be? Calculate it from the table above.
To test if the regression is significant, the parameter of study will be the slope of the regression equation, symbolically: β. If the slope is equal to zero "β=0" then there is no linear regression between the response and explanatory variable. If the slope is different from zero "β≠0" then the regression is significant and the explanatory variable affects the response variable.
The hypotheses are:
H₀: β=0
H₁: β≠0
α: 0.05
The value of the statistic under the null hypothesis is t= 8.48
D.) What can we say about the p-value?
This test is two-tailed and so is the p-value, remember that the p-value is the probabulity of obtaining a value as extreme as the value of the statistic under the null hypothesis. The distribution for this test is a t with n-2= 100-2= 98 degrees of freedom. You can calculate the p-value as:
P(t₉₈≤-8.48) + P(t₉₈≥8.48)= P(t₉₈ ≤ -8.48) + (1 - P(t₉₈ < 8.48) ≅ 0.00001
E.) Ultimately, the reason that we find test statistics is so that we can compare them to a null distribution. For regression, that is a t-distribution based on the degrees of freedom. With 98 degrees of freedom (100-2), we can safely say that the critical t (or the confidence multiplier) is what?
As mentioned before, this test is two tailed, meaning that the rejection region is divided in two:
Critical values ± = ± = ± 1.984
This means that you'll reject the null hypothesis when the statistic is t ≤ -1.984 or if the statistic is t ≥ 1.984-
F.) Find the confidence interval for the slope.
Using a 95% confidence level, the interval for the slope is:
[m ± Sm]
[0.7963 ± 1.984 * 0.0939]
[0.61; 0.98]
G.) Is there a statistically significant relationship? Answer with the test statistic and the confidence interval.
Yes, there is a significant relationship between the width and weight of the horseshoe crabs.
Using the critical value approach:
The calculated statistic is 8.48 and the critical value is ± 1.984, since the statistic is greater than the positive critical value, the decision is to reject the null hypothesis.
If you pay attention to the confidence interval, which was made at a confidence level complementary to the significance level of the hypothesis test, this interval [0.61; 0.98] doesn't include the "zero". Since the interval doesn't include the value of the parameter stated in the null hypothesis, you can conclude that this hypothesis is not true and therefore reject it.
Find the missing length. The triangles are similar.
Answer:
Missing length = 12
Step-by-step explanation:
Let x represent the missing length.
Since the triangles are similar, ∆KLM ~ ∆KRS, therefore, the ratio of their corresponding side lengths would be the same. This implies that:
KL/KR = KM/KS
KL = 65
KR = 65 - 52
KR = 13
KM = 60
KS = x
Plug in the values
65/13 = 60/x
Cross multiply
65*x = 60*13
65x = 780
Divide both sides by 65
65x/65 = 780/65
x = 12
180 °
X °
26 °
X = ? °
Answer:
X = 64
Step-by-step explanation:
All of the angles are right angles (because of the square at one of the angles shown above). This means each angle equals 90 degrees. If X + 26 = 90, then X = 64 because 90 - 26 = 64. I hope this helps!
Answer: X = 64
Step-by-step explanation:
X,and z are midpoints.find the length of each segment
Answers:
MZ = 10ZO = 10MO = 20XZ = 9YZ = 7===========================================
Explanation:
Side MO is twice as long as the midsegment XY. Note how XY and MO are parallel.
This makes
MO = 2*XY = 2*10 = 20
Side MO breaks into two equal halves MZ and ZO
Each of MZ and ZO are 20/2 = 10 units long.
Put another way: XY, MZ and ZO are all the same length (all 10 units long).
---------------
The diagram shows that segment NO is 18 units long, which cuts in half to 18/2 = 9. This is the length of NY, YO and XZ
Also, MN = 14 which cuts in half to 7. This means MX, XN and YZ are all 7 units each.
Solve the equation by graphing. If integral roots cannot be found, estimate the roots by stating the consecutive integers between which the roots lie. -2p2=12p+15
9514 1404 393
Answer:
roots are between -5 and -4, and between -1 and -2.
Step-by-step explanation:
The graph shows the roots are approximately ...
-4.2 — between -5 and -4
-1.8 — between -2 and -1
