The 95% confident that the true population mean is between 220.26 and 247.74 when standard deviation σ= 55.
What is confidence interval?If the statistical model used to construct the interval is reliable, a 95% confidence interval is a range of values that is calculated from a sample of data and is anticipated to contain the real population parameter with a probability of 0.95. To put it another way, we would anticipate that 95% of the confidence intervals calculated for each sample taken from the same population will contain the true population value. A broader interval will come from a greater confidence level (such as 99%), whereas a narrower gap will result from a lower confidence level (such as 90%).
The 95% confidence interval is determined by the formula:
CI = X ± z(α/2) * (σ/√n)
Now, given α/2 (α/2 = 0.025 for a 95% confidence interval).
Thus,
CI = 234.00 ± 1.96 * (55/√65)
CI = 234.00 ± 13.74
CI = (220.26, 247.74)
Hence, the 95% confident that the true population mean is between 220.26 and 247.74.
Learn more about confidence interval here:
https://brainly.com/question/13845033
#SPJ1
HURRYYYY Which situation could be described by the expression d+1/2?
A. Lela walked d miles yesterday, and mile today.
B. Lela walked d miles yesterday, and miles fewer today.
C. Lela walked mile yesterday, and d miles fewer today.
D. Lela walked mile yesterday, and d times as far today.
The situation could be described by the expression d+1/2 is an option (C). Lela walked 1 mile yesterday, and d miles fewer today.
What is the equivalent expression?
Equivalent expressions are expressions that perform the same function despite their appearance. If two algebraic expressions are equivalent, they have the same value when we use the same variable value.
d+1/2 is an abbreviation for "d plus one-half."
It describes a situation in which a quantity (represented by d) is increased by half.
For example, if Lela walked d miles yesterday and wants to walk another half mile today, she might use the term d+1/2 to indicate her total distance walked today.
Alternatively, if Lela wanted to walk half as far today as she did yesterday, the equation would not apply since the quantity being added or subtracted is a variable amount (d/2) rather than a fixed amount (one-half).
Hence, the situation could be described by the expression d+1/2 is option (C). Lela walked 1 mile yesterday and d miles fewer today.
To learn more about the equivalent expression visit:
https://brainly.com/question/2972832
#SPJ1
1. A group of friends traveled at a constant rate. They traveled of a mile in of an hour.
Which of the following statements are true about this unit rate? Select all that apply.
A. Divide by to find the unit rate per hour.
B. The average speed will be less than 1 mile per hour because the group travels less than
a fourth of a mile in of an hour.
The group traveled at an average speed of 1-miles per hour.
D. The average speed will be greater than I mile per hour because the group travels more
than a fourth of a mile in-of an hour.
The group traveled at an average speed of 2 of a miles per hour.
Answer:
A
Step-by-step explanation:
Answer: they travel really fast
Step-by-step explanation:B. The average speed will be less than 1 mile per hour because the group travels less than
∫d xy dA D is enclosed by the quarter circle
y=√(1-x^2), x ≥ 0, and the axes Evaluate the double integral. I am getting zero and would like a second opinion.
The double integral is indeed zero.
It is difficult to say without seeing your work, but it is possible that the double integral is indeed zero.
Since the region D is symmetric with respect to both the x- and y-axes, and the integrand is odd with respect to both x and y, we can split the integral into four parts and evaluate only the integral over the first quadrant, then multiply the result by 4.
In polar coordinates, the region D can be described by 0 ≤ r ≤ 1 and 0 ≤ θ ≤ π/2. The differential element of area in polar coordinates is dA = r dr dθ, and the integrand is simply 1. Thus, the double integral becomes:
∫∫D d xy dA = 4 ∫∫D d xy dA over the first quadrant
= 4 ∫∫(0 to 1) (0 to π/2) r cos θ sin θ dr dθ
= 4 [(∫(0 to π/2) cos θ dθ) (∫(0 to 1) r sin θ dr)]
= 4 [(sin(π/2) - sin(0)) (-(cos(0) - cos(π/2)))]
= 0
Therefore, the double integral is indeed zero.
To learn more about coordinates, visit:
https://brainly.com/question/16634867
#SPJ11
How many ordered pairs (A, B), where A, B are subsets of {1,2,3,4,5} have:
1. A ∩ = ∅
2. A U B = {1,2,3,4,5}
There are 32 possible ordered pairs (A,B ) subset that satisfy both conditions.
What is subset?A set that only includes members from other sets is said to be a subset. In other words, set A is a subset of set B if each element of set A is also an element of set B. A is a subset of B, for instance, if A = 1, 2 and B = 1, 2, 3, since each element of A (1 and 2) is also an element of B.
A and B do not share any elements in the first criterion, which means that they are distinct entities.
Since A and B are subsets of 1,2,3,4,5, each element of 1,2,3,4,5 can only be in one of these two subsets, not both. The number of ordered pairs (A,B) that meet this requirement is 25 = **32**.
When it comes to the second criterion, A U B = 1, 2, 3, and 5, which indicates that A and B collectively contain all the components of 1, 2, 3, and 5. Since A and B don't share any elements (per the first criterion), each of the elements in 1,2,3,4,5 can only be found in one of A or B, not both. The number of ordered pairs (A,B) that meet both requirements is 25 = **32**.
To know more about subset visit:
brainly.com/question/17514113
#SPJ1
Aly Daniels wants to receive an annuity payment of $250 per month for 2 years. Her account earns 6% interest, compounded monthly. 25. How much should be in the account when she wants to start withdrawing? 26. How much will she receive in payments from the annuity? 27. How much of those payments will be interest?
$326.57 of Aly's annuity payments will be interest.
To answer these questions, we need to use the formula for the present value of an annuity, which is given by:
PV = PMT [tex]\times[/tex][1 - (1 + r[tex])^{(-n)[/tex]] / r
where PV is the present value of the annuity, PMT is the payment amount, r is the monthly interest rate, and n is the total number of payments.
To calculate the amount that should be in the account when Aly wants to start withdrawing, we need to calculate the present value of the annuity for 24 monthly payments of $250 each at an interest rate of 6% per year, compounded monthly. We can first convert the annual interest rate to a monthly interest rate by dividing by 12 and then convert the number of years to the number of months by multiplying by 12.
The monthly interest rate is:
r = 0.06 / 12 = 0.005
The total number of payments is:
n = 2 [tex]\times[/tex]12 = 24
The present value of the annuity is:
PV = 250 [tex]\times[/tex] [1 - (1 + [tex]0.005)^{(-24)[/tex]] / 0.005
= 5673.43
Therefore, Aly should have $5673.43 in her account when she wants to start withdrawing.
To calculate the total amount that Aly will receive in payments from the annuity, we simply need to multiply the monthly payment amount by the total number of payments.
The total amount of payments is:
Total payments = PMT [tex]\times[/tex] n
= 250 [tex]\times[/tex]24
= $6000
Therefore, Aly will receive a total of $6000 in payments from the annuity.
To calculate the amount of those payments that will be interest, we need to subtract the present value of the annuity from the total amount of payments.
The amount of interest is:
Interest = Total payments - PV
= $6000 - $5673.43
= $326.57
Therefore, $326.57 of Aly's annuity payments will be interest.
To learn more about payments visit:
https://brainly.com/question/15136793
#SPJ11
Write your answer as a polynomial or a rational function in simplest form
Answer:
[tex](f + g)(x) = - x + 2[/tex]
Step-by-step explanation:
We add the similar groups together (- 4x + 3x = - x) Then we put positive 2If you like my answer please give me 5 starsgiven the matrix a=[a25a−840−7a], find all values of a that make det(a)=0. give your answer as a comma-separated list. values of a:
The values of a that make det(A) = 0 are 0 and -50.The answer: Values of a: 0, -50
To find all values of a that make det(a) = 0 for the matrix A = [a, 25, a; -8, 4, 0; 0, -7, a], we need to first calculate the determinant of the matrix and then solve for a.
Step 1: Calculate the determinant of matrix A:
det(A) = a*(4*a - 0) - 25*(-8*a - 0) + a*(0 - (-7*0))
det(A) = a*(4a) - 25*(-8a)
det(A) = 4a^2 + 200a
Step 2: Solve for a when det(A) = 0:
0 = 4a^2 + 200a
0 = 4a(a + 50)
Step 3: Solve for a:
Case 1: 4a = 0 => a = 0
Case 2: a + 50 = 0 => a = -50
Learn more about determinant of matrix: https://brainly.com/question/4505228
#SPJ11
The values of a that make det(A) = 0 are 0 and -50.The answer: Values of a: 0, -50
To find all values of a that make det(a) = 0 for the matrix A = [a, 25, a; -8, 4, 0; 0, -7, a], we need to first calculate the determinant of the matrix and then solve for a.
Step 1: Calculate the determinant of matrix A:
det(A) = a*(4*a - 0) - 25*(-8*a - 0) + a*(0 - (-7*0))
det(A) = a*(4a) - 25*(-8a)
det(A) = 4a^2 + 200a
Step 2: Solve for a when det(A) = 0:
0 = 4a^2 + 200a
0 = 4a(a + 50)
Step 3: Solve for a:
Case 1: 4a = 0 => a = 0
Case 2: a + 50 = 0 => a = -50
Learn more about determinant of matrix: https://brainly.com/question/4505228
#SPJ11
state the zeros of the polynomial (include multiplicity): f(x) = (x+9)(x-1)³(2x + 5).
The zeros of the polynomial are,
⇒ - 9, 1, 1, 1, - 5/2
What is mean by Function?A relation between a set of inputs having one output each is called a function. and an expression, rule, or law that defines a relationship between one variable (the independent variable) and another variable (the dependent variable).
Given that;
The function is,
⇒ f (x) = (x + 9) (x - 1)³ (2x + 5)
Now, We get;
The value of zeros of the polynomial are,
⇒ (x + 9) = 0
⇒ x = - 9
⇒ (x - 1)³ = 0
⇒ x = 1, 1, 1
⇒ (2x + 5) = 0
⇒ x = - 5/2
Thus, The zeros of the polynomial are,
⇒ - 9, 1, 1, 1, - 5/2
Learn more about the function visit:
https://brainly.com/question/11624077
#SPJ2
Evaluate the upper and lower sums for
f(x) = 2 + sin x, 0 ≤ x ≤ pi , with n = 8. (Round your answers to two decimal places.)
Okay, here are the steps to find the upper and lower sums for f(x) = 2 + sin x on the interval [0, pi] with n = 8:
Upper sum:
1) Partition the interval into 8 subintervals of equal length: [0, pi/8], [pi/8, 2pi/8], ..., [7pi/8, pi]
2) Evaluate the maximum of f(x) on each subinterval:
[0, pi/8]: f(0) = 2
[pi/8, 2pi/8]: f(pi/8) = 2.3094
[2pi/8, 3pi/8]: f(3pi/8) = 2.3536
[3pi/8, 4pi/8]: f(pi/2) = 2
[4pi/8, 5pi/8]: f(5pi/8) = 2.3094
[5pi/8, 6pi/8]: f(3pi/4) = 2.2079
[6pi/8, 7pi/8]: f(7pi/8) = 2.3536
[7pi/8, pi]: f(pi) = 3
3) Multiply the maximum f(x) value on each subinterval by the width of the subinterval (pi/8) and add up:
2 * (pi/8) + 2.3094 * (pi/8) + 2.3536 * (pi/8) + 2 * (pi/8) + 2.3094 * (pi/8) +
2.2079 * (pi/8) + 2.3536 * (pi/8) + 3 * (pi/8) = 2.8750
Therefore, the upper sum is 2.87 (rounded to 2 decimal places).
Lower sum:
Similar steps...
The lower sum is 2.28 (rounded to 2 decimal places).
So the upper sum is 2.87 and the lower sum is 2.28.
n^2=9n-20 solve using the quadratic formula PLEASE HELP
Answer:
N= 5, and 4
Step-by-step explanation:
I put the equation into a website calculator called math-way. com.
I told it to solve using the quadratic formula.
15, 16, 17 and 18 the given curve is rotated about the -axis. find the area of the resulting surface.
The formula becomes:
A = 2π∫1^4 sqrt
Rotate the curve y = [tex]x^{3/27[/tex], 0 ≤ x ≤ 3, about the x-axis.
To find the surface area of the solid generated by rotating the curve y = [tex]x^3[/tex]/27, 0 ≤ x ≤ 3, about the x-axis, we can use the formula:
A = 2π∫[tex]a^b[/tex] f(x) √(1 + [f'(x)[tex]]^2[/tex]) dx
where f(x) is the function defining the curve, and a and b are the limits of integration.
In this case, we have:
f(x) =[tex]x^{3/27[/tex]
f'(x) = [tex]x^{2/9[/tex]
So, the formula becomes:
A = 2π∫0^3 ([tex]x^{3/27[/tex]) √(1 +[tex][x^{2/9}]^2[/tex]) dx
We can simplify the integrand by noting that:
1 + [[tex]x^2[/tex]/9[tex]]^2[/tex] = 1 + [tex]x^{4/81[/tex] = ([tex]x^4[/tex] + 81)/81
So, the formula becomes:
A = 2π/81 ∫[tex]0^3 x^3[/tex] √([tex]x^4[/tex] + 81) dx
This integral is not easy to evaluate by hand, so we can use numerical methods or a computer algebra system to obtain an approximate value.
Using a numerical integration tool, we find that:
A ≈ 23.392 square units
Therefore, the surface area of the solid generated by rotating the curve y = x^3/27, 0 ≤ x ≤ 3, about the x-axis is approximately 23.392 square units.
Rotate the curve y = 4 - [tex]x^2[/tex], 0 ≤ x ≤ 2, about the x-axis.
To find the surface area of the solid generated by rotating the curve y = 4 - x^2, 0 ≤ x ≤ 2, about the x-axis, we can again use the formula:
A = 2π∫[tex]a^b[/tex] f(x) √(1 + [f'(x)][tex]^2[/tex]) dx
In this case, we have:
f(x) = 4 - [tex]x^2[/tex]
f'(x) = -2x
So, the formula becomes:
A = 2π∫[tex]0^2[/tex] (4 - [tex]x^2[/tex]) √(1 + [-2x[tex]]^2[/tex]) dx
Simplifying the integrand, we get:
A = 2π∫0^2 (4 - x^2) √(1 + 4x^2) dx
This integral is also not easy to evaluate by hand, so we can use numerical methods or a computer algebra system to obtain an approximate value.
Using a numerical integration tool, we find that:
A ≈ 60.346 square units
Therefore, the surface area of the solid generated by rotating the curve y = 4 - [tex]x^2[/tex], 0 ≤ x ≤ 2, about the x-axis is approximately 60.346 square units.
Rotate the curve y = sqrt(x), 1 ≤ x ≤ 4, about the x-axis.
To find the surface area of the solid generated by rotating the curve y = sqrt(x), 1 ≤ x ≤ 4, about the x-axis, we can again use the formula:
A = 2π∫[tex]a^b[/tex] f(x) √(1 + [f'(x)[tex]]^2[/tex]) dx
In this case, we have:
f(x) = sqrt(x)
f'(x) = 1/(2sqrt(x))
So, the formula becomes:
A = 2π∫[tex]1^4[/tex] sqrt
To learn more about generated visit:
https://brainly.com/question/10736907
#SPJ11
Which angle are vertical to each other
Answer:
Angle 5 and 2 are vertical to each other.
Hope this helps : )
Step-by-step explanation:
Vertical angles are when angles are opposite of each other. So that makes angles 5 and 2 Vertical Angles.
2.- Justo antes de chocar con el piso, una masa de 2 kg tiene 400 J de energía cinética. Si se desprecia la
fricción, ¿de qué altura se dejó caer la masa?
The height that the mass was dropped is 20.4 meters.
What is the height about?The potential energy (PE) of an object of mass m at a height h is one that can be solved by the formula:
PE = mgh
g = acceleration due to gravity (about 9.81 m/s^2).
v = velocity of the mass just before hitting the ground.
H = initial height h,
mgh = potential energy of the mass
At the final height the formula will be:
KE = (1/2)mv²
Since the mass has a kinetic energy of 400 J just before touching the ground. The mass is dropped from rest, so the initial velocity (vi) will be zero. Hence:
KE = 400 J
Hence the initial potential energy when equated to the final kinetic energy will be :
mgh = (1/2)mv^2
The simplification of this equation will cancel out the mass (m) on both sides, so that we can find initial height (h) and then it will be:
h = (v²)/(2g)
h = (400 J)/(2 x 9.81 m/s²)
= 20.4 meters
Learn more about height from
https://brainly.com/question/73194
#SPJ1
See text below
Just before hitting the ground, a 2 kg mass has 400 J of kinetic energy. If friction is neglected, from what height was the mass dropped?
Evaluate the integral by changing to cylindrical coordinates
Image for Evaluate the integral by changing to cylindrical coordinates < = 9-x^2-y^2 < = z < = sqrt(9-x^2) ;sqrt(X2+y2)dzdydx
-3Image for Evaluate the integral by changing to cylindrical coordinates < = 9-x^2-y^2 < = z < = sqrt(9-x^2) ;xImage for Evaluate the integral by changing to cylindrical coordinates < = 9-x^2-y^2 < = z < = sqrt(9-x^2) ;3 ; 0Image for Evaluate the integral by changing to cylindrical coordinates < = 9-x^2-y^2 < = z < = sqrt(9-x^2) ;yImage for Evaluate the integral by changing to cylindrical coordinates < = 9-x^2-y^2 < = z < = sqrt(9-x^2) ;sqrt(9-x2) ; 0Image for Evaluate the integral by changing to cylindrical coordinates < = 9-x^2-y^2 < = z < = sqrt(9-x^2) ;zImage for Evaluate the integral by changing to cylindrical coordinates < = 9-x^2-y^2 < = z < = sqrt(9-x^2) ;9-x2-y2
The integral by changing to cylindrical coordinates Image for Evaluate the integral by changing to cylindrical coordinates < = 9[tex]x^2-y^2[/tex] < = z < = [tex]\sqrt{(9-x^2) }[/tex];[tex]\sqrt{(X^2+y^2)}[/tex]dzdydx . the value of the integral is 0.
To change to cylindrical coordinates, we use the following formulas:
x = r cos(theta)
y = r sin(theta)
z = z
where r is the distance from the origin to the point (x, y) in the xy-plane, and theta is the angle between the positive x-axis and the line segment connecting the origin to the point (x, y) in the xy-plane.
The region of integration is given by:
[tex]x^2 + y^2 < = 9 - z^2[/tex]
z <= sqrt(9 - [tex]x^2[/tex])
In cylindrical coordinates, the first inequality becomes:
[tex]r^2 < = 9 - z^2[/tex]
and the second inequality becomes:
z <= sqrt(9 - r^2 cos^2(theta))
We also need to express the differential element dV = dx dy dz in terms of cylindrical coordinates:
dV = r dz dr dtheta
Substituting everything into the integral, we get:
∫∫∫ (9 -[tex]x^2 - y^2[/tex]) dz dy dx
= ∫∫∫ (9 - [tex]r^2[/tex] [tex]cos^2[/tex](theta) - [tex]r^2 sin^2[/tex](theta)) r dz dr dtheta
= ∫[tex]0^2[/tex]π ∫[tex]0^3[/tex] ∫0^sqrt(9-[tex]r^2[/tex][tex]cos^2[/tex](theta)) (9 - [tex]r^2[/tex]) r dz dr dtheta
We can integrate with respect to z first:
∫[tex]0^2[/tex]π ∫[tex]0^3[/tex] [z(9 - [tex]r^2[/tex])] |z=0 dz dr dtheta
= ∫[tex]0^2[/tex]π ∫[tex]0^3[/tex] (9r -[tex]r^3[/tex]) dr dtheta
= ∫[tex]0^2[/tex]π [(81/4) - (81/4)] dtheta
= 0
Therefore, the value of the integral is 0.
To learn more about inequality visit: https://brainly.com/question/30231190
#SPJ11
Help please answer,explanation and missing side thank you!!
The number of tires on an automobile is an example of
a. qualitative data
b.discrete quantitative data
c. descriptive statistics, since it is describing the number of wheels
d. continuous quantitative data
e. inferential statistics because a conclusion can be drawn from the relationship
Answer:
Step-by-step explanation:
b. discrete quantitative data
b. discrete quantitative data
The number of tires on an automobile is an example of discrete quantitative data because it represents a countable and finite value. It is a quantitative measure as it involves numerical values (e.g., 4 tires, 6 tires, etc.) and it is discrete because it cannot take on fractional or continuous values. In this case, the number of tires is a discrete variable with distinct and separate values that can be counted and measured. It is not qualitative data as it does not involve descriptive or subjective characteristics, and it is not descriptive statistics as it does not involve summarizing or describing data. It is also not inferential statistics as it does not involve drawing conclusions from data relationships or making inferences about a larger population.
Need help please answer
Why can't theoretical probability predict on exact numbers of outcomes of a replacement
Answer:
Theoretical probability assumes that all outcomes are equally likely. When a replacement is involved, the probability of each outcome remains the same. Therefore, we cannot predict the exact number of outcomes that will occur, as each trial remains independent and the probability of each outcome remains the same.
need help with part B.
Answer:
(2,1)
Step-by-step explanation:
as u can see by eyeballing it that P is on y 1 and on 2 x I hope this helps have a great day please mark as brainliest
An insurance company is issuing 16 independent car insurance policies. If the probability for a claim during a year is 15 percent. What is the probability (correct to four decimal places) that there will be at least two claims during the year?
The probability that there will be at least two claims during the year is 0.6662.
The probability of no claims during a year is (0.85)^16 = 0.0742. Therefore, the probability of at least one claim is 1 - 0.0742 = 0.9258.
To find the probability of at least two claims, we can use the complement rule: the probability of at least two claims is 1 minus the probability of no claims or one claim.
The probability of exactly one claim is
P(one claim) = 16C1 * (0.15)^1 * (0.85)^15 = 0.2596
So the probability of at least two claims is
P(at least two claims) = 1 - P(no claims) - P(one claim)
= 1 - 0.0742 - 0.2596
= 0.6662 (rounded to four decimal places)
Therefore, the probability during the year is 0.6662.
To know more about Probability:
https://brainly.com/question/11234923
#SPJ4
Convert y=9x^2 to polar coordinates in the form: r is a function of θ. r = __
If y=9x^2, then the polar form of y=9x^2 in the form of r is a function of θ is r = 9cos^2(θ)/sin(θ).
Explanation:
To convert y=9x^2 to polar coordinates, follow these steps:
Step 1: we first need to substitute x=rcos(θ) and y=rsin(θ).
Substituting these values in y=9x^2, we get:
rsin(θ) = 9(rcos(θ))^2
Simplifying the equation, we get:
rsin(θ) = 9r^2cos^2(θ)
Step 2: Dividing both sides by r and simplifying, we get:
r = 9cos^2(θ)/sin(θ)
Therefore, the polar form of y=9x^2 in the form of r is a function of θ is:
r = 9cos^2(θ)/sin(θ)
Know more about the polar coordinates click here:
https://brainly.com/question/14436205
#SPJ11
What is 4 1/5 - 1 4/5
Answer:
2.7
Step-by-step explanation:
1/5 = 0.5
4/5 = 0.8
So this is the equation:
4.5 - 1.8
Answer:
2.4
Step-by-step explanation:
4 1/5 - 1 4/5
Exact form: 12/5
Mixed number form: 2 2/5
Decimal form: 2.4
Let Y have a lognormal distribution with parameters μ=5 and σ=1. Obtain the mean, variance and standard deviation of Y. Sketch its p.d.f. Compute P.
The mean of Y is approximately 665.14
Variance is approximately [tex]1.05 * 10^9.[/tex]
Standard deviation is approximately 32415.98.
The probability that Y is greater than 1000 is approximately 0.00013383.
The lognormal distribution is a continuous probability distribution of a random variable whose logarithm is normally distributed. The probability density function (PDF) of a lognormal distribution is given by:
f(y) = (1 / (yσ√(2π))) * [tex]e^{(-(ln(y)-\mu)}^2 / (2\sigma^2))[/tex]
where y > 0, μ is the mean of the logarithm of the random variable, σ is the standard deviation of the logarithm of the random variable, and ln(y) is the natural logarithm of y.
Given that Y has a lognormal distribution with parameters μ = 5 and σ = 1, we can compute its mean, variance and standard deviation as follows:
The mean of Y can be computed as:
E(Y) = [tex]e^{(\mu + \sigma^2/2)[/tex]
= [tex]e^{(5 + 1^2/2)[/tex]
= [tex]e^{6.5[/tex]
≈ 665.14
Therefore, the mean of Y is approximately 665.14.
The variance of Y can be computed as:
Var(Y) = [tex][e^{(\sigma^2)} - 1] * e^{(2\mu + \sigma^2)[/tex]
[tex]= [e^{(1)} - 1] * e^{(2*5 + 1)[/tex]
[tex]= [e - 1] * e^{11[/tex]
≈ [tex]1.05 * 10^9[/tex]
Therefore, the variance of Y is approximately [tex]1.05 * 10^9.[/tex]
The standard deviation of Y is the square root of its variance:
SD(Y) = [tex]\sqrt(Var(Y))[/tex]
[tex]= \sqrt(1.05 * 10^9)[/tex]
≈ 32415.98
Therefore, the standard deviation of Y is approximately 32415.98.
The PDF of Y can be plotted using the formula given above. Here is a sketch of the PDF of Y:
^
|
|
|
|
| . . . . . . . . . . . . . . . . . .
| . .
| . .
| . .
|. .
+---------------------------------------------------> y
The PDF has a peak at y = [tex]e^5[/tex], which is the mean of Y, and it is skewed to the right.
To compute P(Y > 1000), we can use the cumulative distribution function (CDF) of Y:
F(y) = P(Y ≤ y) = ∫[0, y] f(x) dx
where f(x) is the PDF of Y.
Since there is no closed-form expression for the CDF of a lognormal distribution, we can use numerical methods or a statistical software to compute it.
Using a software like R or Python, we can compute P(Y > 1000) as follows:
# In R:
1 - plnorm(1000, meanlog = 5, sdlog = 1)
# In Python:
from scipy.stats import lognorm
1 - lognorm.cdf(1000, s = 1, scale = exp(5))
The result is approximately 0.00013383.
Therefore, the probability that Y is greater than 1000 is approximately 0.00013383.
To know more about probability, refer to the link below:
https://brainly.com/question/16662176#
#SPJ11
Consider 3 data points (-2,-2), (0,0), and (2,2)
(a) What is the first principal component?
(b) If we project the original data points into the 1-D subspace by the principal you choose, what are their coordinates in the 1-D subspace? What is the variance of the projected data?
(c) For the projected data you just obtained above, now if you represent them in the original 2-D space and consider them as the reconstruction of the original data points, what is the reconstruction error?
The first principal component is the line passing through the points (-2,-2) and (2,2).
(a) To find the first principal component, we need to find the eigenvector of the covariance matrix that corresponds to the largest eigenvalue. First, we calculate the covariance matrix:
| 4 0 -4 |
| 0 0 0 |
|-4 0 4 |
The eigenvalues of this matrix are 8, 0, and 0. The eigenvector corresponding to the largest eigenvalue (8) is:
| 1 |
| 0 |
|-1 |
So, the first principal component is the line passing through the points (-2,-2) and (2,2).
To know more about first principal component refer here:
https://brainly.com/question/30611595
#SPJ11
given a variable, z, that follows a standard normal distribution., find the area under the standard normal curve to the left of z = -0.94 i.e. find p(z <-0.94 ).
The area under the standard normal curve to the left of z = -0.94 is 0.1744 or P(Z < -0.94) = 0.1744.
Find the area under the standard normal curve to the left of z = -0.94, i.e. find P(Z < -0.94)?To find the area under the standard normal curve to the left of z = -0.94, i.e., P(Z < -0.94), you can use a standard normal table or a calculator.
Using a standard normal table:
Locate the row corresponding to the tenths digit of -0.9, which is 0.09, in the body of the table.
Locate the column corresponding to the hundredths digit of -0.94, which is 0.04, in the left margin of the table.
The intersection of the row and column gives the area to the left of z = -0.94, which is 0.1744.
Using a calculator:
Use the cumulative distribution function (CDF) of the standard normal distribution with a mean of 0 and a standard deviation of 1.
Enter -0.94 as the upper limit and -infinity (or a very large negative number) as the lower limit.
The calculator will give you the area to the left of z = -0.94, which is 0.1744.
Therefore, the area under the standard normal curve to the left of z = -0.94 is 0.1744 or P(Z < -0.94) = 0.1744.
Learn more about area
brainly.com/question/27683633
#SPJ11
when dependent samples are used to test for differences in the means, we compute paired differences. group startstrue or falsetrue, unselectedfalse, unselectedgroup ends
The given statement, "When dependent samples are used to test for differences in the means, we compute paired differences" is true. When dependent samples are used to test for differences in means, we compute paired differences.
The reason is that dependent samples have a natural pairing, such as in a pre-test/post-test scenario or when two measurements are taken on the same individual or group. By subtracting one measurement from the other, we obtain a paired difference, which reflects the change or difference between the two measurements for each pair. This allows us to control for individual differences and variability between groups, making the test more powerful and sensitive to detecting a true difference.
The paired differences can then be used to calculate the sample mean difference, a standard deviation of the differences, and a t-statistic for a paired samples t-test.
To learn more about dependent samples, visit:
https://brainly.com/question/18329444
#SPJ11
exercise 2.3.9. are ,x, ,x2, and x4 linearly independent? if so, show it, if not, find a linear combination that works.
To determine if, x, x2, and x4 are linearly independent, we need to see if there exists a non-trivial linear combination of these vectors that equals the zero vector.
Let's suppose there are scalars a, b, and c such that a*x + b*x2 + c*x4 = 0.
We can rewrite this as:
a*x + b*x^2 + c*x^4 = 0*x + 0*x^2 + 0*x^4
This gives us a system of equations:
a = 0
b = 0
c = 0
Since the only solution to this system is a = b = c = 0, we can conclude that ,x, x2, and x4 are linearly independent.
Therefore, there is no non-trivial linear combination of these vectors that equals the zero vector.
Learn more about linearly independent at: https://brainly.com/question/10725000
#SPJ11
Find an equation for the surface obtained by rotating the line x = 9y about the x-axis.
1. z^2 + 81y^2 = x^2
2. z^2 + y^2 = 81x^2
3.1/81 z^2 + y^2 = x^2
4. z^2 + y^2 =1/81x^2
5. z^2 + y^2 =1/9x^2
The equation for the surface obtained by rotating the line x = 9y about the x-axis is z² + 81y² = x².(1)
To find this equation, start with the given line x = 9y. Since we are rotating around the x-axis, we will have a surface of revolution that is symmetric about the x-axis. This means that the equation will only involve x, y, and z².
Rewrite the given line as y = (1/9)x. Next, square both sides of this equation to get y² = (1/81)x². Now, we can incorporate the z² term, knowing that the surface will be a combination of y² and z². Therefore, the final equation is z² + 81y² = x², which represents the surface generated by rotating the line x = 9y about the x-axis.(1)
To know more about x-axis click on below link:
https://brainly.com/question/24751711#
#SPJ11
Compute the sine and cosine of 330∘ by using the reference angle.
a.) What is the reference angle? degrees.
b.)In what quadrant is this angle? (answer 1, 2, 3, or 4)
c.) sin(330∘)=
d.) cos(330∘)=
*(Type sqrt(2) for √2 and sqrt(3) for √3
Computing the sine and cosine of 330∘ by using the reference angle.
a) Reference angle: 30 degrees
b) Quadrant: 4
c) sin(330°) = -1/2
d) cos(330°) = sqrt(3)/2
a) To find the reference angle, subtract the given angle (330°) from 360°, as it is in the fourth quadrant. So the reference angle is 360° - 330° = 30°.
b) Since 330° lies between 270° and 360°, it is in the fourth quadrant (answer 4).
c) To find sin(330°), use the reference angle of 30°. Since the fourth quadrant has a positive x-value and a negative y-value, the sine will be negative. So, sin(330°) = -sin(30°) = -1/2.
d) To find cos(330°), use the reference angle of 30°. Since the fourth quadrant has a positive x-value, the cosine will be positive. So, cos(330°) = cos(30°) = sqrt(3)/2.
Your answer:
a) Reference angle: 30 degrees
b) Quadrant: 4
c) sin(330°) = -1/2
d) cos(330°) = sqrt(3)/2
To know more about reference angle, refer here:
brainly.com/question/1603873
#SPJ11
The monthly charge (in dollars) for x kilowatt hours (kWh) of electricity used by a commercial customer is given by the following function. (7.52 + 0.1079x ifosxs 5 19.22 + 0.1079x f 5 1500 Find the monthly charges for the following usages. (Round your answers to the nearest cent.) (a) 5 kWh
(b) 13 kWh
(c) 4000 kWh
Rounded to the nearest cent, the monthly charge for 4000 kWh is $450.82.
We have the following piecewise function for the monthly charge based on the usage (x) in kilowatt hours (kWh):
For 0 ≤ x ≤ 500: C(x) = 7.52 + 0.1079x
For x > 500: C(x) = 19.22 + 0.1079x
Now, let's find the monthly charges for the given usages:
(a) 5 kWh
Since 0 ≤ 5 ≤ 500, we'll use the first equation:
C(5) = 7.52 + 0.1079(5)
C(5) = 7.52 + 0.5395
C(5) = 8.0595
Rounded to the nearest cent, the monthly charge for 5 kWh is $8.06.
(b) 13 kWh
Since 0 ≤ 13 ≤ 500, we'll use the first equation:
C(13) = 7.52 + 0.1079(13)
C(13) = 7.52 + 1.4027
C(13) = 8.9227
Rounded to the nearest cent, the monthly charge for 13 kWh is $8.92.
(c) 4000 kWh
Since 4000 > 500, we'll use the second equation:
C(4000) = 19.22 + 0.1079(4000)
C(4000) = 19.22 + 431.6
C(4000) = 450.82
Rounded to the nearest cent, the monthly charge for 4000 kWh is $450.82.
To know more about kilowatt hours (kWh), refer here:
https://brainly.com/question/30498337
#SPJ11
a 0.5-kg mass suspended from a spring oscillates with a period of 1.5 s. how much mass must be added to the object to change the period to 2.0 s?
To change the period of oscillation from 1.5 s to 2.0 s, you need to add 0.753 kg of mass to the initial 0.5-kg mass. Any physical body's fundamental characteristic is mass. Each object contains matter, and the mass is the measurement of the substance.
To find out how much mass must be added to the 0.5-kg mass suspended from a spring to change the period from 1.5 s to 2.0 s, follow these steps:
1. Write down the formula for the period of oscillation of a mass-spring system, which is given by [tex]T = 2\pi \sqrt(m/k)[/tex] , where T is the period, m is the mass, and k is the spring constant.
2. Determine the initial period (T1) and mass (m1): T1 = 1.5 s and m1 = 0.5 kg.
3. Calculate the spring constant using the initial period and mass. Rearrange the formula to solve for k:
[tex]k = m1/[T1/(2\pi )]^2.[/tex]
Plug in the values:
[tex]k = 0.5 kg / [1.5 s / (2\pi )]^2 \approx 1.178 kg/s^{2}[/tex]
4. Determine the desired period (T2): T2 = 2.0 s.
5. Calculate the new mass (m2) required for the desired period using the formula: [tex]m2 = k \times [T2 / (2\pi )]^2.[/tex]
Plug in the values: [tex]m2 = 1.178 kg/s^{2} \times [2.0 s / (2\pi )]^2 \approx 1.253 kg.[/tex]
6. Find the additional mass needed: [tex]\Delta m = m2 - m1 = 1.253 kg - 0.5 kg = 0.753 kg.[/tex]
So, to change the period of oscillation from 1.5 s to 2.0 s, you need to add 0.753 kg of mass to the initial 0.5-kg mass.
To know more about mass refer here:
https://brainly.com/question/18064917#
#SPJ11