The manager of a fleet of automobiles is testing two brands of radial tires and assigns one tire of each brand at random to the two rear wheels of eight cars and runs the cars until the tires wear out. The data (in kilometers) follow. Find a 99% confidence interval on the difference in the mean life.
Car Brand 1 Brand 2
1 36663 33866
2 43509 41829
3 36240 35500
4 32100 31950
5 37210 38015
6 48360 47800
7 38200 37810
8 33500 33215
a) Calculate SD =
b) Calculate a 99% two-sided confidence interval on the difference in mean life.
c) Which brand would you prefer? (brand 1/ no difference /brand 2)_____
Answer:
a) σ = 4933,64
b) CI 99% = ( - 5746 ; 7194 )
c) No difference in brands
Step-by-step explanation:
Brand 1:
n₁ = 8
x₁ = 38222
s₁ = 4974
Brand 2:
n₂ = 8
x₂ = 37498
s₂ = 4893
As n₁ = n₂ = 8 Small sample we work with t -student table
degree of freedom df = n₁ + n₂ - 2 df = 8 +8 -2 df = 14
CI = 99 % CI = 0,99
From t-student table we find t(c) = 2,624
CI = ( x₁ - x₂ ) ± t(c) * √σ²/n₁ + σ²/n₂
σ² = [( n₁ - 1 ) *s₁² + ( n₂ - 1 ) * s₂² ] / n₁ +n₂ -2
σ² = 7* (4974)² + 7*( 4893)² / 14
σ² = 24340783 σ = 4933,64
√ σ²/n₁ + σ²/n₂ = √ 24340783/8 + 24340783/8
√ σ²/n₁ + σ²/n₂ = 2466
CI 99% = ( x₁ - x₂ ) ± 2,624* 2466
CI 99% = 724 ± 6470
CI 99% = ( - 5746 ; 7194 )
As we can see CI 99% contains 0 and that means that there is not statistical difference between mean life of the two groups
Use the method of cylidrincal shells to find the volume of the solid generated by rotating the region bounded by the curves y=6x-2x^2 and y=x^2 about the y axis.
Find where the two curves intersect:
y = 6x - 2x ²
y = x ²
6x - 2x ² = x ² → 3x ² - 6x = 3x (x - 2) = 0 → x = 0 and x = 2
Now, for a shell of radius x units away from the axis of revolution, the height of the shell would be the vertical distance between the upper curve and the lower curve. For 0 ≤ x ≤ 2, we have 6x - x ² ≥ x ², so the height of any given shell is (6x - x ²) - x ² = 6x - 2x ².
Then volume of the solid is
[tex]\displaystyle 2\pi \int_0^2 x(6x-2x^2)\,\mathrm dx = 2\pi \left(2x^3-\frac{x^4}2\right)\bigg|_0^2 = \boxed{16\pi}[/tex]
what is the smallest subset of the number -8,546,999 belong to
Answer:
its 4
Step-by-step explanation:
Can someone please help me
Answer: 120cm squared
Step-by-step explanation: To do this you can cut off one of the 'triangle ends' on the trapezoid and add it to the other side to make a rectangle. Since the top is 10cm, each triangle will have a base of 5cm, so the bases will be 15cm when you subtract 20-5. Then you just have 8 * 15 which is 120cm SQUARED. This may have been a little confusing so i attachecd a diagram.
Abigail ordered a 32 oz steak that cost $60.
(cost to weight)
find the asymptotes, domain, range and end behavior and sketch the parent graph with the translated graph
Answer:
27) x = 2^(y) – 5.
Asymptote: x = -5.
D: x > -5; (-5, infinity).
R: -infinity < f(x) < infinity; ARN;
(-infinity, infinity).
x → -infinity, f(x) → -infinity.
x → +infinity, f(x) → +infinity.
________________________
28) x = 2^-(y–3).
Asymptote: x = 0.
D: x > 0; (0, infinity).
R: -infinity < f(x) < infinity; ARN;
(-infinity, infinity).
x → -infinity, f(x) → +infinity.
x → +infinity, f(x) → -infinity.
________________________
29) x = 4^(y–2) + 1.
Asymptote: x = 1.
D: x > 1; (1, infinity).
R: -infinity < f(x) < infinity; ARN;
(-infinity, infinity).
x → -infinity, f(x) → -infinity.
x → +infinity, f(x) → +infinity.
________________________
When graphed on a coordinate plane Beth’s house is located at (4, 3) and the coffee shop is located at the point (–2, –1).
What is the distance from Beth’s house to the coffee shop? Each grid line on the coordinate plane represents 1 mile.
10 miles
square root of 8
square root of 52
52 miles
Answer:
the answer is c square root 52
Step-by-step explanation:
just got a 100
The distance from Beth’s house to the coffee shop, which are graphed on a coordinate plane is √(52) units.
What is a distance formula?The distance formula is used to measure the distance between the two points on a coordinate plane.
Let the two coordinate point on a coordinate plane is ([tex]x_1,y_1[/tex]) and ([tex]x_2,y_2[/tex]). Thus, the distance between these two can be given as,
[tex]d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}[/tex]
When graphed on a coordinate plane Beth’s house is located at (4, 3) and the coffee shop is located at the point (–2, –1).
Here, each grid line on the coordinate plane represents 1 mile.
Using the distance formula for these point, the distance from Beth’s house to the coffee shop can be given as,
[tex]d=\sqrt{(4-(-2)^2)+(3-(-1))^2}\\d=\sqrt{6)^2+(4)^2}\\d=\sqrt{36+16}\\d=\sqrt{52}[/tex]
Hence, the distance from Beth’s house to the coffee shop, which are graphed on a coordinate plane is √(52) units.
Learn more about the distance formula here;
https://brainly.com/question/661229
sum of -4/5 and -5/12. please answer.
Answer:
[tex]- 1 \frac{13}{60} [/tex]
Step-by-step explanation:
[tex] - \frac{4}{5} + - \frac{5}{12} \\ \frac{ - 48 - 25}{60} \\ \frac{ - 73}{60} \\ = - 1 \frac{13}{60} [/tex]
Hope this helps you.
Can I have the brainliest please?
Does anybody know the answer to this question
Answer:
A
Step-by-step explanation:
PLS HELP
Find the volume.
Answer:
V= 160 ft
Step-by-step explanation:
First 10×8×6 then ÷ 3 = 160
Help please and thanks <33
Answer:
The 4th one (bottom)
Step-by-step explanation:
[tex]\frac{2}{3}x - 5 > 3\\\frac{2}{3}x > 3 + 5\\\frac{2}{3}x > 8\\x > 8 / \frac{2}{3} \\x > 12\\[/tex]
> sign means an open circle over 12, shaded/pointing to the right. The 4th option is your answer
Verify the conclusion of Green's Theorem by evaluating both sides of the equation for the field F= -2yi+2xj. Take the domains of integration in each case to be the disk. R: x^2+y^2 < a^2 and its bounding circle C.
Answer:
hello your question is incomplete below is the complete question
verify the conclusion of Green's Theorem by evaluating both sides of the equation for the field F= -2yi+2xj. Take the domains of integration in each case to be the disk. R: x^2+y^2 < a^2 and its bounding circle C: r(acost)i+(asint)j, 0<t<2pi. the flux is ?? the circulation is ??
answer : attached below
Step-by-step explanation:
Attached below is the required verification of the conclusion of Green's Theorem
In the attached solution I have proven that Green's theorem ( ∫∫c F.Dr ) .
i.e. ∫∫ F.Dr = ∫∫r ( dq/dt - dp/dy ) dx dy = 4πa^2
Given a polynomial f(x), if (x + 7) is a factor, what else must be true
Answer:
Step-by-step explanation:
at x = -7, the polynomail function f(x) has a zero (x-intercept)
(4x-1)2=11
whats the solution
Answer:
x = 13/8
Step-by-step explanation:
(4x−1)(2)=11
Simplify both sides of the equation.
(4x−1)(2)=11
(4x)(2)+(−1)(2)=11 (Distribute)
8x+−2=118x+−2=11
8x−2=11
Add 2 to both sides.
8x−2+2=11+2
8x=13
Divide both sides by 8.
8x/8 = 13/8
which brings you to the answer of
x = 13/8
(Note:If this was a little confusing,feel free to ask me any questions revolving around this topic)
The sum of 2 numbers is 11 and the difference is 5
Answer:
let no. be x and y.
we have
x+y=11.......(1)
x-y=5........(2)
adding equation 1&2
x+y+x-y=11+5
2x=16
x=16/2=8
again
8-y=5
y=8-5=3
:.
x=8,y=3
Litter such as leaves falls to the forest floor, where the action of insects and bacteria initiates the decay process. Let A be the amount of litter present, in grams per square meter, as a function of time t in years. If the litter falls at a constant rate of L grams per square meter per year, and if it decays at a constant proportional rate of k per year, then the limiting value of A is R = L/k. For this exercise and the next, we suppose that at time t = 0, the forest floor is clear of litter.
Required:
If D is the difference between the limiting value and A, so that D = R - A, then D is an exponential function of time. Find the initial value of D in terms of R.
Answer:
D = L/k
Step-by-step explanation:
Since A represents the amount of litter present in grams per square meter as a function of time in years, the net rate of litter present is
dA/dt = in flow - out flow
Since litter falls at a constant rate of L grams per square meter per year, in flow = L
Since litter decays at a constant proportional rate of k per year, the total amount of litter decay per square meter per year is A × k = Ak = out flow
So,
dA/dt = in flow - out flow
dA/dt = L - Ak
Separating the variables, we have
dA/(L - Ak) = dt
Integrating, we have
∫-kdA/-k(L - Ak) = ∫dt
1/k∫-kdA/(L - Ak) = ∫dt
1/k㏑(L - Ak) = t + C
㏑(L - Ak) = kt + kC
㏑(L - Ak) = kt + C' (C' = kC)
taking exponents of both sides, we have
[tex]L - Ak = e^{kt + C'} \\L - Ak = e^{kt}e^{C'}\\L - Ak = C"e^{kt} (C" = e^{C'} )\\Ak = L - C"e^{kt}\\A = \frac{L}{k} - \frac{C"}{k} e^{kt}[/tex]
When t = 0, A(0) = 0 (since the forest floor is initially clear)
[tex]A = \frac{L}{k} - \frac{C"}{k} e^{kt}\\0 = \frac{L}{k} - \frac{C"}{k} e^{k0}\\0 = \frac{L}{k} - \frac{C"}{k} e^{0}\\\frac{L}{k} = \frac{C"}{k} \\C" = L[/tex]
[tex]A = \frac{L}{k} - \frac{L}{k} e^{kt}[/tex]
So, D = R - A =
[tex]D = \frac{L}{k} - \frac{L}{k} - \frac{L}{k} e^{kt}\\D = \frac{L}{k} e^{kt}[/tex]
when t = 0(at initial time), the initial value of D =
[tex]D = \frac{L}{k} e^{kt}\\D = \frac{L}{k} e^{k0}\\D = \frac{L}{k} e^{0}\\D = \frac{L}{k}[/tex]
The body temperatures of all mosquitoes in a county have a mean of 57∘F and a standard deviation of 10∘F. What is the probability that in a sample of 25 mosquitoes the mean body temperature is greater than 59∘F, assuming the underlying distribution is normal? Do not write probability in terms of percentage. Round your answer to two decimal places.
Answer:
0.16 probability that in a sample of 25 mosquitoes the mean body temperature is greater than 59∘F, assuming the underlying distribution is normal.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
The body temperatures of all mosquitoes in a county have a mean of 57∘F and a standard deviation of 10∘F.
This means that [tex]\mu = 57, \sigma = 10[/tex]
Sample of 25:
This means that [tex]n = 25, s = \frac{10}{\sqrt{25}} = 2[/tex]
of 25 mosquitoes the mean body temperature is greater than 59∘F, assuming the underlying distribution is normal?
This is 1 subtracted by the pvalue of Z when X = 59. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{59 - 57}{2}[/tex]
[tex]Z = 1[/tex]
[tex]Z = 1[/tex] has a pvalue of 0.84
1 - 0.84 = 0.16
0.16 probability that in a sample of 25 mosquitoes the mean body temperature is greater than 59∘F, assuming the underlying distribution is normal.
de una bolsa donde hay veinte bolas numeradas del 1 al 20 extraemos una, A: obtener un número par , B: obtener número primo, C: obtener un número tal que su suma de cifras sea 5,
a) comprobar que cumplan con las propiedades asociativa y distributiva en los sucesos, b) comprobar que se cumplan con las propiedades de las leyes de morgan entre los sucesos AyC , ByC, AyB , c) efectúa las siguientes operaciones en los sucesos unión entre AB, BC, AB, intersección entre AB,BC, AB, diferenciación entre AB, BA, CA, AC,
IF A FUNCTION f(x) is defined AS 5x^2-3x+3, what is the expression for
Answer: C. 10x-3
Step-by-step explanation: I got this question correct on Edmentum.
The value of the expression will be 10x – 3. Then the correct option is C.
What is the limit?The value that approaches the output for the given input value. Limits are a very important tool in calculus.
The function is defined as,
f(x) = 5x² – 3x + 2
Then the value of the expression will be
[tex]\rightarrow \displaystyle \lim_{h \to 0} \dfrac{f(x+h)-f(x)}{h}[/tex]
Substitute the value of the function, then the value of the expression will be
[tex]\rightarrow \displaystyle \lim_{h \to 0} \dfrac{5(x+h)^2 - 3(x + h) + 3- 5x^2 + 3x - 3}{h}\\\\\\\rightarrow \displaystyle \lim_{h \to 0} \dfrac{5x^2 + 5h^2 + 10xh - 3x - 3h + 3- 5x^2 + 3x - 3}{h}\\\\\\\rightarrow \displaystyle \lim_{h \to 0} \dfrac{ 5h^2 + 10xh - 3h }{h}\\[/tex]
Simplify the equation further, then we have
[tex]\rightarrow \displaystyle \lim_{h \to 0} 5h + 10x - 3 \\[/tex]
Substitute the value of the h = 0, then the value of the expression will be
⇒ 5(0) + 10x – 3
⇒ 10x – 3
Then the correct option is C.
More about the limit link is given below.
https://brainly.com/question/8533149
#SPJ2
Ethan purchased a new cell phone for $75.00. The costs of the phone is included in his first month's bill. His cell phone plan charges $0.06 for each minute used.
if Ethan has $90.00 to spend on his first month's bill, what is the maximum number of minutes he can use?
A. 80 minutes
B. 250 minutes
C. 1,250 minutes
D. 1,500 minutes
Answer:1,250
Step-by-step explanation:
Which of the following points are solutions to the equation 3x - 4y - 8 = 12?
Select all that apply.
(0-5)
(82)
(-16-17)
(-1,-8)
(-40,-34)
Sorry I did it wrong.
Answer:
(0, -5) and (-16, -17)
Step-by-step explanation:
You can plug in the points into the function to test them.
(0, -5)
3(0) - 4(-5) - 8 = 12
20 - 8 = 12
12 = 12
(8, 2)
3(8) - 4(2) - 8 = 12
24 - 8 - 8 = 12
8 ≠ 12
(-16, -17)
3(-16) - 4(-17) - 8 = 12
-48 + 68 - 8 = 12
12 = 12
3(-1) - 4(-8) - 8 = 12
-3 + 32 - 8 = 12
21 ≠ 12
3(-40) - 4(-34) - 8 = 12
-120 + 136 - 8 = 12
8 ≠ 12
A tour helicopter travels at a constant rate of 80 mph. If the tour takes 2 hours, how far does the helicopter travel?
A. 40 mi.
B. 80 mi.
C. 120 mi.
D. 160 mi.
Answer:
D
Step-by-step explanation:
80 miles per hour, each hour it will travel 80 miles so for two hours tou do
80 x 2 = 160
Answer:
D
Step-by-step explanation:
80x2=40
it's just simple multiplecation but then again I cant spell multiplication so I mean
A piecewise function is given.
Find f(-4)
Answer:
3
Step-by-step explanation:
For x<=0, f is constant: f(x) =3
-4<0, so f(-4)=3
(MATH) (6) ((PHOTO))
label is m
Multiply the length by the height:
6.5 x 2 = 13
The width is the volume divided by 13
Width = 52/13 = 4 m
.............................................
Step-by-step explanation:
.........................
.......
Through extensive data collection, quality control experts have verified that the true mean weight of a wrapped Starburst candy is 5.1 grams, as advertised on the package. However, in a class activity where you selected and weighed 8 wrapped Starburst candies you obtained a p-value of 0.003 and concluded that the true mean weight of Starburst candies is not as advertised. What type of error was potentially made in this hypothesis test
Answer:
Type 1 error.
Step-by-step explanation:
H0 : μ = 5.1
H1 : μ ≠ 5.1
The Pvalue of the test = 0.003
Decision made by the researcher was conclude that mean weight is not as advertised, that is the researcher rejected the Null hypothesis.
However, when the Pvalue is < α - value , we reject the null ; The type of error the researcher could have made is that ; The mean weight may be truly as advertised, Hence, leading us to make a false positive error, thus is rejecting a true null. This is a TYPE 1 error.
A store pay $120 for a bicycle. The store has a 60% markup policy. What is the selling price of the bicycle?
Answer:
$192
Step-by-step explanation:
Quadrilateral K is the image of Quadrilateral K under a dilation
Can someone help me with this question plz show work.
Answer:
d
Step-by-step explanation:
V=whl=3·4·6=72
D. 6*4*6≠72
Answer:
D 6x6x4
Step-by-step explanation:
the dimensions are 3x6x4 so 6x6x4 is not the volume of this rectangular prism
this is a nice question for 69 points (nice)
What's 34.5 x 2
A. 45
B. nice
C. 78
D. 50
Answer:
34.5 × 2 = 69
Step-by-step explanation:
pretty self explanatory