Answer: 80
Step-by-step explanation:
# Wrong Grade
1 90
2 80
3 70
4 60
Find the angle between vector bold lower u equals 3 bold lower I plus start root 3 end root bold lower j and vector bold lower v equals negative 2 bold lower I minus 5 bold lower j to the nearest degree. A. 82° B. 38° C. 142° D. 98°
Answer:
C. 142°
Step-by-step explanation:
You want the angle between vectors u=3i+√3j and v=-2i-5j.
AngleThere are a number of ways the angle between the vectors can be found. For example, the dot-product relation can give you the cosine of the angle:
u•v = |u|·|v|·cos(θ) . . . . . . where θ is the angle of interest
You can find the angles of the vectors individually, and subtract those:
u = |u|∠α
v = |v|∠β
θ = α - β
When the vectors are expressed as complex numbers, the angle between them is the angle of their quotient:
\(\dfrac{\vec{u}}{\vec{v}}=\dfrac{|\vec{u}|\angle\alpha}{|\vec{v}|\angle\beta}=\dfrac{|\vec{u}|}{|\vec{v}|}\angle(\alpha-\beta)=\dfrac{|\vec{u}|}{|\vec{v}|}\angle\theta\)
This method is used in the calculation shown in the first attachment. The angle between u and v is about 142°.
A graphing program can draw the vectors and measure the angle between them. This is shown in the second attachment.
__
Additional comment
The approach using the quotient of the vectors written as complex numbers is simply computed using a calculator with appropriate complex number functions. There doesn't seem to be any 3D equivalent.
The dot-product relation will work with 3D vectors as well as 2D vectors.
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Without graphing, answer the following questions for each of the functions below: F(x) = x^2 + 8x^3 + k F (x) = x^6 + kx^4 - 9x^2 - 27 f (x) = -1/2x^7 - 441x^3 + k What are the end behaviours of this type of function (what quadrant does it begin and end in?) What is the maximum and minimum number of x-What is the maximum and minimum number of turns for this type of function? State if thereintercepts for this type of function? are any restrictions on the domain and range on this type of function
F(x) = x^2 + 8x^3 + k
End behavior: As x approaches positive or negative infinity, F(x) approaches positive infinity.
Maximum/minimum: There is no global maximum or minimum without more information about k.
x-intercepts: There are no x-intercepts for this function.
Restrictions on domain and range: No restrictions specified.
What are the responses for other questions?F(x) = x^6 + kx^4 - 9x^2 - 27
End behavior: As x approaches positive or negative infinity, F(x) approaches positive infinity.
Maximum/minimum: There is no global maximum or minimum without more information about k.
x-intercepts: There are no x-intercepts for this function.
Restrictions on domain and range: No restrictions specified.
f(x) = -1/2x^7 - 441x^3 + k
End behavior: As x approaches positive or negative infinity, f(x) approaches negative infinity.
Maximum/minimum: There is no global maximum or minimum without more information about k.
x-intercepts: There are no x-intercepts for this function.
Restrictions on domain and range: No restrictions specified.
The number of turns and the maximum and minimum number of x-intercepts for this type of function can't be determined without a graph.
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A scuba diver descends farther down into the ocean from an initial depth of 15.2 feet below sea level. The scuba diver descends at a constant rate for 2 1/2 minutes and reaches a depth no more than 46.7 feet below sea level. What is the maximum rate, r, that the scuba diver may descend?
r ≤ 24 19/25
r ≥ 24 19/25
r ≤ 12.6
r ≥ 12.6
The maximum rate, r, that the scuba diver may descend is r ≤ 12.6
A linear equation is in the form:
y = mx + b;
where y, x are variable, m is the slope of the line and b is the y intercept.
Let r represent the rate. Since the initial depth is 15.2 feet below sea level, hence b = -15.2. Also, it reaches a depth no more than 46.7 feet below sea level within 2 1/2 (2.5 minutes). therefore:
2.5r - 15.2 ≤ -46.7
2.5r ≤ -31.5
r ≤ -12.6
r ≤ 12.6 (descending)
The maximum rate, r, that the scuba diver may descend is r ≤ 12.6
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Answer:
K12 Answer
Step-by-step explanation:
The mean annual salary of a sample of 225 office managers is $46,130 with a standard deviation of $2,980. Calculate the margin of error and construct the 80% confidence interval for the true population mean annual salary for office managers. We may assume that the sample standard deviation s is an accurate approximation of the population standard deviation σ (i.e. s=σ ). given that the sample size is so large (n>200). E= Round'to the nearest dollar <μ< Rougd to the nearest dollar
Margin of error: $776.56Construct the 80% confidence interval: $45,353.44 < μ < $46,906.56
Margin of error (E) can be calculated as:
Where; z is the z-score corresponding to the level of confidence, σ is the population standard deviation, n is the sample size, and E is the margin of error.
So, for an 80% confidence interval, z = 1.282. Putting the values in the above formula, we get:
E = $776.56 (rounded off to the nearest dollar)Construct the 80% confidence interval:The lower limit of the confidence interval can be calculated as:And, the upper limit of the confidence interval can be calculated as:
So, the 80% confidence interval for the true population mean annual salary for office managers is:$45,353.44 < μ < $46,906.56 (rounded off to the nearest dollar)
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Determine the point estimate of the population mean and margin of
error for the confidence interval with lower bound 19 and upper bound: 27.
Using confidence interval concepts, it is found that:
The point estimate of the population mean is of 23.The margin of error is of 4.Given a confidence interval what are the point estimate of the population mean and the margin of error?A confidence interval has two bounds, a lower bound and an upper bound.A confidence interval is symmetric, which means that the point estimate used is the mid point between these two bounds, that is, the mean of the two bounds.The margin of error is the difference between the two bounds, divided by 2.In this problem, the interval is (19,27), hence the point estimate is:
P = (19 + 27)/2 = 23.
The margin of error is:
M = (27 - 19)/2 = 4.
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Please help I will give brainliest
Answer:
92 degrees
C
Step-by-step explanation:
the least squares method for determining the best fit minimizes
The least squares method minimizes the sum of the squared differences between the observed data points and the predicted values.
The least squares method is a mathematical technique used to find the best fit line or curve for a set of data points. It is commonly used in regression analysis to determine the relationship between two variables.
The method works by minimizing the sum of the squared differences between the observed data points and the predicted values from the line or curve. This sum is known as the residual sum of squares (RSS) or the sum of squared residuals (SSR).
The least squares method aims to find the line or curve that minimizes this sum, meaning it minimizes the overall error between the observed data and the predicted values. By minimizing the sum of squared differences, the method finds the line or curve that best represents the data.
In other words, the least squares method seeks to find the line or curve that provides the best balance between fitting the data closely and avoiding extreme deviations from the data points.
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The least squares method for determining the best fit minimizes the sum of the squared differences between the observed data points and the corresponding values predicted by the mathematical model or regression line.
In other words, it aims to minimize the sum of the squared residuals, where the residual is the difference between the observed data point and the predicted value. By minimizing the sum of squared residuals, the least squares method finds the line or curve that best fits the data by minimizing the overall error between the predicted values and the actual data.
Mathematically, the least squares method minimizes the objective function:
E = Σ(yᵢ - ŷᵢ)²
where yᵢ is the observed value, ŷᵢ is the predicted value, and the summation Σ is taken over all data points. The goal is to find the values of the parameters in the mathematical model that minimize this objective function, usually by differentiating it with respect to the parameters and setting the derivatives equal to zero.
By minimizing the sum of squared differences, the least squares method provides a way to estimate the parameters of a mathematical model that best represents the relationship between the independent and dependent variables in a data set.
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A store is offering a 25% discount on all electronics during a special weekend sale. Marcia wants to buy a television that regularly costs p dollars. She has written the expression 0. 75p to represent the sale price. Which is the best description for her expression?.
Marcia has written the expression 0. 75p to represent the sale price. The best description for her expression is she multiplied p by 0.25 then subtracted that from p.
How to express the sale price?
The sale price is the price after discount. Discount is the amount by which the origin price of an item is reduced. In this case, Marcia wants to buy a television with the origin prices is p dollars. The store is offering 25% discount.
p = the origin price
25% discount = 0.75p
The sale price = p - (0.25p)
So, the best description for Marcia's expression is multiplied p by 0.25 then subtracted that from p.
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there are 6 men and 4 women in a union chapter. how many ways are there to select 3 men and 2 women for a committee
Answer:
Step-by-step explanation:
To determine the number of ways to select 3 men and 2 women for a committee from a union chapter consisting of 6 men and 4 women, we can use the concept of combinations.
The number of ways to select 3 men from 6 men is given by the combination formula: C(6, 3) = 6! / (3! * (6 - 3)!) = 20.
Similarly, the number of ways to select 2 women from 4 women is given by the combination formula: C(4, 2) = 4! / (2! * (4 - 2)!) = 6.
To obtain the total number of ways to select 3 men and 2 women for the committee, we multiply these two combinations together: 20 * 6 = 120.
Therefore, there are 120 ways to select 3 men and 2 women for a committee from the given union chapter.
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A boy has 800 he spends 160 what fraction of his original money does he have left
Answer:
Step-by-step explanation:
800-160=640
640/800=64/80
64/80=16/20
16/20=4/5
Answer=4/5
The fraction of his original money does he have left = 4/5 .
What is a fraction in math?
A fraction is a part of a whole. In arithmetic, the number is expressed as a quotient, in which the numerator is divided by the denominator. In a simple fraction, both are integers. A complex fraction has a fraction in the numerator or denominator. In a proper fraction, the numerator is less than the denominator.A boy has = 800 and spends = 160
800-160=640
640/800=64/80
64/80=16/20
16/20=4/5
Therefore, his original money left =4/5
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what is the value of x in the rhombus below
Answer: 12.5
Step-by-step explanation:
Charlotte is going to drive from her house to City A without stopping. An
equation that determines Charlotte's distance from City At hours after
leaving her house is D = -30t +300. What is the y-intercept of the
equation and what is its interpretation in the context of the problem?
Answer: To find Y intercept means
T=0, so replace T with 0 and solve equation
it is equal to
300
Here is what I did to find the answer, If have any other question add me on discord Acathia#0103, i can help you with any other problems
Steve has been saving dimes and quarters out of his pocket change for two weeks.He then notices that he has 53 coins for a total of $8.45.How many of each kind of coin does he have?
The number of quarters that Steve has is 21.
The number of dimes that Steve has is 32.
How many of each kind of coin does he have?The first step is to form a pair of linear equations using the information in the question:
d + q = 53 equation 1
0.1d + 0.25q = 8.45 equation 2
Where:
d = number of dimes q = number of quartersThe system of equations would be solved using the elimination method: Multiply equation 1 by 0.1 :
0.1d + 0.1q = 5.3 equation 3
Subtract equation 3 from equation 2:
0.15q = 3.15
Divide both sides of the equation by 0.15:
q = 3.15 / 0.15
q = 21
In order to determine the value of d, substitute for q in equation 1:
21 + d = 53
d = 53 - 21
d = 32
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Sue has 18 sweets.
Tony also has 18 sweets.
Sue gives Tony X sweets.
Sue then eats 5 of her sweets.
Tony then eats half of his sweets.
Write expressions for the number of sweets Sue and Tony now have?
Sue=?
Tony=?
Describe the transformation of the function f(x)=2|x+3| from its parent function. WHOEVER HELPS ME I WILL MARK BRAINLEST :)
Parent function is general modulus function
y=|x|Now
x is increased by +3 so change in x axis and vertex.
The vertex shifted 3 units leftwards .
And it's multiplied with 2Means compression factor is 2
Both graphs attached
Answer:
Translated 3 units leftStretched parallel to the y-axis (vertically) by a scale factor of 2
Step-by-step explanation:
Translations
For \(a > 0\)
\(f(x+a) \implies f(x) \: \textsf{translated}\:a\:\textsf{units left}\)
\(y=a\:f(x) \implies f(x) \: \textsf{stretched parallel to the y-axis by a factor of}\:a\)
Parent function: \(f(x) = |x|\)
Translated 3 units left: \(f(x+3)=|x+3|\)
Stretched parallel to the y-axis by a factor of 2: \(2f(x+3)=2|x+3|\)
Therefore, the function has been:
Translated 3 units leftStretched parallel to the y-axis (vertically) by a scale factor of 2Attachments
Green graph - parent function \(f(x) = |x|\)
Red graph - Translated 3 units left \(f(x)=|x+3|\)
Blue graph - Stretched \(f(x)=2|x+3|\)
Could someone please help me this is due at 3 pm and it's allready 2:43 and i only need these questions and i am done please help me. if you answer all you get 20 points! PLEASE HELP PLEASE HELP ANYONE PLEASE PLEASE
a) (2.3 × \($10^4\)) × (1.5 × \($10^{-2}\)) in standard form
The number in standard form is 345
explanation:
The given two multiplication of the numbers is :
(2.3 × \($10^4\)) × (1.5 × \($10^{-2}\))
First we multiply the non exponential terms as shown below
2.3 × 1.5 = 3.45
Now we multiply the exponential terms as shown below
\($10^4\) × \($10^{-2}\) = 100
Now multiplying the exponential and non exponential term we get the number in standard form as shown below
(2.3 × \($10^4\)) × (1.5 × \($10^{-2}\)) in standard form 345
(3.6 × \(10^-5\))÷(1.8 × 10²) in standard form 0.0000002
(8 × 10^-3) × (2 × \(10^-4\) in standard form 1.6 × \(10^-6\)
(6 × 10²)/(3 × 10-5) in standard form 20,00,0000
5.1 × \($10^-1\) in ordinary number is 0.51
(1.7 × \(10^4\)) × (8.5x ×\(0^-2\)) in standard form 1.445 × 10³.
3.45 x 100 = 345
Therefore, the number in the standard form is 345
b) (3.6 × \(10^-5\))÷(1.8 × 10²) in standard form
The number in standard form is 0.0000002
explanation:
By dividing 3.6 by 1.8 we get “2”, hence the above equation becomes,
(2 × \(10^-5\)) /\(10^2\)
We know that
\(\frac{x^{a} }{x^{b} } = x^{a-b}\)
Therefore the above equation becomes,
2 × \(10^-7\)
since the exponent of 10 is negative , therefore 7 zeros are written on the left hand side of the number = 0.0000002
Therefore, the number in the standard form is 0.0000002
c) (8 × \(10^-3\)) × (2 × \(10^-4\)) in standard form
The number in standard form is 1.6 × \(10^-6\)
explanation:
Given the product of scientific notations:
(8 × \(10^-3\)) × (2 × \(10^-4\))
This can be expressed as:
(8 × 2) × (\(10^-3\) × \(10^-4\))
= 16 × \(10^-3\)-4
= 16 × \(10^-7\)
= 1.6 × \(10^1\) × \(10^-7\)
= 1.6 × \(10^-6\)
Therefore, the number in the standard form is 1.6 × \(10^-6\)
d) (6 × 10²)/(3 × 10-5) in standard form
The number in standard form is 20,00,0000
e) 5.1 × 10^-1 as an ordinary number
The ordinary number is 0.51
usual form of 5.1 × \(10^1\) is
5.1 × 1/ \(10^1\)
= 5.1/10
= 0.51
Therefore , ordinary number is 0.51
f) (1.7 × \(10^4\)) × (8.5 × \(10^-2\)) in standard form.
The number in standard form is 1.445 × 10³.
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2. Find the equation of the tangent line to each curve at the given point. a. \( \quad f(x)=4^{x},(0,1) b. \( \quad {y}=\frac{x}{\ln x^{\prime}} , \( (2.718,2.718)
\(a. The function given is `f(x) = 4^x` and the point at which we need to find the tangent line is `(0,1)`\)
\(The first derivative of the function is given by: `f'(x) = 4^x ln4`\)
To find the slope of the tangent at the point `(0,1)`, we substitute the value of `x = 0` in the first derivative: Slope of the \(tangent `= f'(0)``= 4^0 ln4 = ln4`\)
The equation of the tangent line passing through the point `(0,1)` is given by `y = mx + c`, where `m` is the slope of the tangent line and `c` is the `y`-intercept.
\(Thus, the equation of the tangent line is :'y = ln4x + 1`b. The function given is `y = x/ln(x')` and the point at which we need to find the tangent line is `(2.718, 2.718)`\)
\(Here, we have `e` as the base of the natural logarithm, and the derivative of the function is given by: `y' = [(ln x') - x/(x' ln x')] / ln^2(x')`\)
\(The value of the derivative at the given point `(2.718, 2.718)` is:`y' = [(ln e) - 1/e] / ln^2(e)``= (1 - 1/e) / ln^2(e)`\)
slope of the tangent at the point `(2.718, 2.718)` is equal to the value of the derivative at that point, which is:`\(y' = (1 - 1/e) / ln^2(e)`\)
\(The equation of the tangent line passing through the point `(2.718, 2.718)` is given by `y = mx + c`,\)where `m` is the slope of the tangent line and `c` is the `y`-intercept.
\(Thus, the equation of the tangent line is:`y = [(1 - 1/e) / ln^2(e)](x - 2.718) + 2.718`\)
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To find the equation of the tangent line to the curve \(\(f(x) = 4^x\)\) at the point (0, 1), we can use the derivative of the function.
The derivative of \(\(f(x) = 4^x\)\) can be found using the chain rule. Let's calculate it:
\(f'(x) &= \frac{d}{dx} (4^x)\)
\(= \ln(4) \cdot 4^x\)
Now, we have the slope of the tangent line at any point on the curve. To find the equation of the tangent line at the point (0, 1), we'll substitute the x-coordinate (0) and the y-coordinate (1) into the point-slope form of the line.
Using the point-slope form of a line: \(\(y - y_1 = m(x - x_1)\)\),
where \(\((x_1, y_1)\)\) is the given point and (m) is the slope, we have:
\(y - 1 &= (\ln(4) \cdot 4^0)(x - 0)\)
\(y - 1 = \ln(4) \cdot x\)
\(y = \ln(4) \cdot x + 1\)
Therefore, the equation of the tangent line to the curve \(\(f(x) = 4^x\)\) at the point (0, 1) is \(\(y = \ln(4) \cdot x + 1\)\)
b. To find the equation of the tangent line to the curve \(\(y = \frac{x}{\ln x}\)\)at the point (2.718, 2.718), we can use the derivative of the function.
The derivative of \(\(y = \frac{x}{\ln x}\)\) can be found using the quotient rule. Let's calculate it:
\(y' = \frac{d}{dx} \left(\frac{x}{\ln x}\right)\)
\(= \frac{\ln x - 1}{(\ln x)^2}\)
Now, we have the slope of the tangent line at any point on the curve. To find the equation of the tangent line at the point (2.718, 2.718), we'll substitute the x-coordinate (2.718) and the y-coordinate (2.718) into the point-slope form of the line.
Using the point-slope form of a line:\(\(y - y_1 = m(x - x_1)\)\),
where\(\((x_1, y_1)\)\)is the given point and (m) is the slope, we have:
\(y - 2.718 &= \left(\frac{\ln(2.718) - 1}{(\ln(2.718))^2}\right)(x - 2.718)\)
\(y - 2.718 &= \frac{\ln(2.718) - 1}{(\ln(2.718))^2}(x - 2.718)\)
\(y = \frac{\ln(2.718) - 1}{(\ln(2.718))^2}(x - 2.718) + 2.718\)
Therefore, the equation of the tangent line to the curve
\(\(y = \frac{x}{\ln x}\)\)
at the point (2.718, 2.718) is:
\({(\ln(2.718))^2}(x - 2.718) + 2.718\)\)
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neeeeeeeeeeed helpppppppppp
The answer is true.
Complementary = 90
Supplementary = 180
Answer:
true
Step-by-step explanation:
What are the zeros of the function h (x) = x² + 3x - 8?
A
x = -8 and x = -2
OB
x= -8 and x = 2
cx = -2 and x = 8
OD x = 2 and x = 8
The following are the zeros for the function h (x) = x2 + 3x - 8: - x= -4 and x=2.
Describe functions.Given a collection of inputs X (domain) and a set of potential outputs Y (codomain), a function is more technically defined as a set of ordered pairings (x,y) where xX and yY with the caveat that there can only be one ordered pair with the same value of x. The function notation f:XY can be used to express that f is a function from X to Y.
The function's zero is a value of x that makes it equal to zero. In other words, the equation f(x) = 0 leads to a zero.
By putting h(x) equal to zero and figuring out x, we may determine the zeroes for the function h(x) = x2 + 3x - 8.
h(x) = x² + 3x - 8 = 0
We may factor the left side of the equation to find x:
x² + 3x - 8 = (x-2)(x+4) = 0
We set each factor to zero and solve for x to discover the zeroes:
x-2 = 0 or x+4 = 0
x = 2 or x = -4
Consequently, the function's zeros are x = 2 and x = -4.
So, A is the right response. x = -4 and x = 2
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The complete question is
What are the zeros of the function h (x) = x² + 3x - 8?
A. x = -4 and x = -2
B. x= -8 and x = 2
C. x = -2 and x = 8
D. x = 2 and x = 8
If area of a rhombus is 336 cm and one of its diagonal is 14 cm, find its perimeter.
Answer:
The perimeter of the Rhombus is 100 cm
Step-by-step explanation:
First of all, we will need to find the length of the other diagonal.
let’s call the diagonals p and q
Mathematically, the area of the Rhombus is;
pq/2 = Area of Rhombus.
Let’s call the missing diagonal p
So;
(p * 14)/2 = 336
14p = 672
p = 672/14
p = 48 cm
Now, we can find the perimeter of the Rhombus using these diagonals.
Mathematically;
P = 2 √(p^2 + q^2)
Substituting these values, we have;
P = 2 √(14)^2 + (48^2)
P = 2 √(2500)
P = 2 * 50
P = 100 cm
The perimeter of the rhombus is the sum of its side lengths
The perimeter of the Rhombus is 100 cm
The length of one of its diagonal is given as:
\(p= 14\)
And the area is given as:
\(A = 336\)
Assume the other diagonal is q.
The area of the rhombus is represented as:
\(A = \frac{pq}2\)
So, we have:
\(336 = \frac{14q}2\)
This gives
\(336 = 7q\)
Divide both sides by 7
\(48 = q\)
Rewrite as:
\(q = 48\)
The perimeter (P) of the rhombus is calculated as:
\(P =2\sqrt{p^2 + q^2\)
So, we have:
\(P =2\sqrt{48^2 + 14^2\)
Evaluate the squares
\(P =2\sqrt{2500\)
Take positive root of 2500
\(P =2 \times 50\)
\(P =100\)
Hence, the perimeter of the Rhombus is 100 cm
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Hint: your answer will be a fraction or decimal. ex: 3/5 or 0.6 *
Find the probability that a point chosen at random on the part of the number line shown will lie
between points B and C.
On solving the provided question we can say that - the probability of the event will be there are two red sides, thus multiplying 16.6667 by two results in 33.3333%.
What is probability?A branch of mathematics known as probability measures the possibility of an event happening or a proposition being true. The probability of an occurrence is a number between 0 and 1, where roughly 0 denotes the event's improbability and 1 denotes certainty. A probability is a numerical representation of the possibility or probability that a specific event will take place. Probabilities can alternatively be stated as percentages ranging from 0% to 100%, or as percentages from 0 to 1. the proportion between the number of events in a comprehensive collection of equally likely outcomes that lead to a certain occurrence and the entire number of outcomes.
Each side would be 50%, and if one side were divided among three people, it would equal 16.6667 per person.
Given that there are two red sides, you can multiply 16.6667 by 2 to get 33.3333%.
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(i) Let Y be the ratio of net FDI as a proportion of GDP for 70 different developed and developing countries in the world for year 2017. The model to be estimated is the following:
Yi=β1+β2X2i+β3X3i+β4X4i+ui
Where X2 log of per capita GDP; X3 is the log of square of per capita GDP and X4 is the proportion of population in the 20-60 years who have completed graduation. (i) State all the assumptions of the classical linear regression model to estimate the above model and indicate which assumption is violated in the above model when the regressors X2, X3 and X4 are defined in the above manner. (6 marks)
(ii) Suppose you estimate the model: Yi=β1+β2X2i+ui
However, the true model should also have the explanatory variable X4 as given below:
Yi=α1+α2X2i+α3X4i+ui
Derive the omitted variable bias in β2 compared to α2 and show that β2=α2 if X2 and X4 are not correlated.
(i) Assumptions of classical linear regression: linearity, independence, homoscedasticity, no perfect multicollinearity, zero conditional mean, and normality. Violation: perfect multicollinearity between X2, X3, and X4.
(ii) Omitted variable bias occurs when X4 is omitted from the model, leading to a biased estimate of β2 compared to α2 if X2 and X4 are correlated.
In the given model, the assumption of no perfect multicollinearity is violated when the regressors X2, X3, and X4 are defined as the log of per capita GDP, the log of the square of per capita GDP, and the proportion of population with graduation, respectively. X3 is a function of X2, and X4 may be correlated with both X2 and X3. This violates the assumption that the independent variables are not perfectly correlated with each other.
Omitted variable bias in β2 compared to α2 occurs when X4 is omitted from the model. This bias arises because X4 is a relevant explanatory variable that affects the dependent variable (Y), and its omission leads to an incomplete model. The bias in β2 arises from the correlation between X2 and X4. If X2 and X4 are not correlated, β2 will equal α2, and there will be no omitted variable bias. However, if X2 and X4 are correlated, omitting X4 from the model will result in a biased estimate of β2 because the omitted variable (X4) affects both Y and X2, leading to a bias in the estimation of the relationship between Y and X2.
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a 174-foot-long fence is being placed around the perimeter of a rectangular swimming pool that has a 3-foot-wide sidewalk around it. the actual swimming pool without the sidewalk is twice as long as it is wide. find the dimensions of the pool without the sidewalk
The dimensions of the swimming pool without the sidewalk are:
Length = 58 feet and Width = 29 feet.
The formula perimeter = 2(length + width) can be used to compute the perimeter of a rectangle, which is equal to twice the sum of its length and width. It is stated in linear measures like centimeters, inches, yards, and the like and represents the measurement of the entire rectangle's boundaries.
The perimeter of the rectangular swimming pool is 174 feet.
The width of the rectangular swimming pool is 3 feet.
Now without the sidewalk, the length is twice as long as its width.
Let L be the length and W be the width.
Then,
L = 2W
The perimeter of the rectangle is given as:
Perimeter = 2( L + W )
174 = 2( 2W + W )
174 = 2( 3W)
174 = 6W
W = 29 feet
Then, the length of the pool without the sidewalk is:
L = 2W
L = 2( 29 ) = 58 feet
The dimensions of the pool are 58 feet × 29 feet.
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Please help, Brainly and 20 PTS to whoever gets it right
Answer:
decrease income
Step-by-step explanation:
income is already lower than expenses so lowering it further is the worst you can do out of all 4
Simply the product.
(2y – 5)(3y + 1)
A. 6y2 + 13y - 5
B. 6y2 – 13y - 5
C. 6y2 + 17y + 5
D. 6y2 – 13y + 5
Answer:
6y2 - 13y - 5............
A researcher wants to know if a new type of exercise improves people’s health. Would this be a one-tailed or a two-tailed test and why?
a) One-tailed because the study is only interested in whether exercise increases health. b) One-tailed because the study only looks at the effects of exercise and does not take other factors into account. c) Two-tailed because they will have to study healthy and unhealthy people. d) Two-tailed because there is no predicted direction of the difference.
Two-tailed because there is no predicted direction of the difference. The correct answer is D.
In hypothesis testing, a one-tailed test is used when the researcher has a specific prediction about the direction of the effect. They expect the results to be either greater than or less than a certain value. However, in this scenario, the researcher simply wants to investigate whether the new type of exercise improves people's health without any specific directional prediction.
A two-tailed test is appropriate when the researcher wants to determine if there is a significant difference between the groups being compared, but without specifying the direction of the difference. In this case, the researcher wants to examine if the new exercise has any effect on health, whether it improves or worsens it. Therefore, a two-tailed test is suitable as it allows for the possibility of observing a significant difference in either direction.
Therefore, considering these factors, the researcher should conduct a two-tailed test to assess the potential impact of the new exercise on people's health. The correct answer is D.
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Key Terms
Confidence level: probability that the population mean or proportion falls within the confidence interval
Confidence interval: the region formed between a point estimate minus the margin or error and the point estimate plus the margin of error
A confidence level is a statistical term that refers to the probability that a population mean or proportion falls within a specific range of values, called the confidence interval. The confidence level is typically expressed as a percentage and is based on the level of certainty desired by the researcher or decision-maker.
A confidence interval is a range of values around a point estimate, such as a sample mean or proportion, that is likely to contain the true population parameter with a specified level of confidence. The confidence interval is constructed by taking the point estimate and adding and subtracting the margin of error, which is based on the standard error of the estimate and the desired level of confidence.
For example, if we estimate the mean height of a population to be 65 inches with a margin of error of 2 inches and a 95% confidence level, the confidence interval would be [63, 67]. This means that we are 95% confident that the true population mean height falls between 63 and 67 inches.
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need a quick answer please
What's the question?
Just tell me and I will edit this answer.
Answer:
ok tell me brahhh
Step-by-step explanation:
The perimeter of a rectangle is 36 units. the width, w, of the rectangle is 8 units.which equation correctly relates the given information and the length
The length of the given rectangle is 10 units.
Here, we are given that the perimeter of a rectangle is 36 units.
A rectangle is a figure with 4 sides and opposite sides equal. The perimeter of a rectangle is calculated using the given formula-
Perimeter = 2 ( length + breadth )
Here, the breadth (width) is given to be 8 units.
Let the length be x units.
Then, we can form the following equation-
Perimeter = 2( x + 8 )
36 = 2x + 16
36 - 16 = 2x
20 = 2x
2x = 20
x = 20/2
x = 10
Thus, the length of the given rectangle is 10 units.
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You are building a rectangular dog pen with the length is twice as long as the width. You have 120 feet of fencing what are the dimensions of the dog pen?
Answer:
Dimensions are 20 + 20 + 40 + 40
Step-by-step explanation: