A motorboat is able to travel at a speed of 20km/hr in still water. In 8 hours, the boat traveled 20km against the current and 180km with the current. Find the speed of the current

Answers

Answer 1

Answer:

10 km/hr.

Step-by-step explanation:

Speed of the boat with the current = 20 + c   where c is the speed of the current.

Against the current the speed is 20 - c.

Distance = speed * time :

With the current:

180 = (20 + c)t..........A

Against the current:

20 = (20 - c)(8- t)......B

Solving this system of equations:

From A:

t = 180/(20 + c)

So

20 = (20 - c)(8 - 180/(20+c))

160 - 3600/(20 + c) - 8c  + 180c/(20 + c) = 20

Mltiplying throagh by (20 + c):

160(20 + c) - 3600 - 8c(20 + c) + 180c = 20(20 + c)

3200 + 160c - 3600 - 160c - 8c^2 + 180c - 400 - 20c = 0

-8c^2 + 160c  - 800 = 0

8c^2 - 160c + 800 = 0

c^2 - 20c + 100 = 0

(c - 10)*2 = 0

c = 10

So the speed of the crrent = 10 km/hr


Related Questions

A random variable X has pdf:
fx(x)={c(1−x2)−1 ≤ x ≤ 1
0 otherwise
(a) Find c and sketch the pdf.
(b) Find and sketch the cdf of X.

Answers

c = 1/2, and the pdf is fx(x) = { 1/2 [tex](1-x^{2} )^{-1}[/tex], −1 ≤ x ≤ 1or 0 otherwise and cdf of X is: FX(x) = { 0, x ≤ -1 or -1/2 [tex]tan^{-1}(x/\sqrt{1-x^{2} )}[/tex] + 1/2, -1 < x < 1 or 1 ,x ≥ 1

(a) To find c, we need to integrate the pdf over its support and set the result equal to 1 since the pdf must integrate to 1 over its entire support. Therefore, we have:

1 = ∫c [tex](1-x^{2} )^{-1}[/tex] dx from -1 to 1

Using the substitution u = 1 - [tex]x^{2}[/tex], we have:

1 = c∫ [tex]u^{-1/2}[/tex] dx from 0 to 1

Solving the integral, we get:

1 = 2c

Therefore, c = 1/2, and the pdf is:

fx(x) = {

1/2 [tex](1-x^{2} )^{-1}[/tex] , −1 ≤ x ≤ 1

0 otherwise

To sketch the pdf, we can notice that it is symmetric about x = 0 and that it approaches infinity as x approaches ±1. Therefore, it will have a peak at x = 0 and decrease as we move away from x = 0 in either direction.

(b) To find the cdf of X, we can integrate the pdf from negative infinity to x for each value of x in the support of the pdf. Therefore, we have:

FX(x) = ∫fX(t) dt from -∞ to x

For x ≤ -1, FX(x) = 0, since the pdf is zero for x ≤ -1. For -1 < x < 1, we have:

FX(x) = ∫1/2 [tex](1-t^{2} )^{-1}[/tex] dt from -1 to x

Using the substitution u = [tex]t^{2}[/tex] - 1, we have:

FX(x) = -1/2 ∫[tex](x^{2} -1)^{-1/2}[/tex] du

Solving the integral, we get:

FX(x) =  -1/2 [tex]tan^{-1}(x/\sqrt{1-x^{2} )}[/tex]  + 1/2

For x ≥ 1, we have FX(x) = 1, since the pdf is zero for x ≥ 1. Therefore, the cdf of X is:

FX(x) = {

0 x ≤ -1

-1/2 [tex]tan^{-1}(x/\sqrt{1-x^{2} )}[/tex]  + 1/2 -1 < x < 1

1 x ≥ 1

To sketch the cdf, we can notice that it starts at 0 and increases gradually from x = -1 to x = 1, where it jumps to 1. The cdf is also symmetric about x = 0, similar to the pdf.

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Is a trapezoid a quadrilateral or parallelogram or both? Explain.

Answers

Answer: both

Step-by-step explanation:

The height y (in feet) of a ball thrown by a child is y=−1/16x^2+6x+3 where x is the horizontal distance in feet from the point at which the ball is thrown. (a) How high is the ball when it leaves the child's hand? (Hint: Find y when x=0) 1- Your answer is y= 2- What is the maximum height of the ball? 3- How far from the child does the ball strike the ground?

Answers

(a) The ball is 3 feet high when it leaves the child's hand.                      

(b) The maximum height of the ball is 75 feet.

(c) The ball strikes the ground approximately 91.6 feet from the child

How to find the height of the ball?

(a) To find the height of the ball moving in a projectile motion when it leaves the child's hand, we need to substitute x = 0 into the equation and solve for y:

[tex]y = -1/16(0)^2 + 6(0) + 3[/tex]

y = 3

Therefore, the ball is 3 feet high when it leaves the child's hand.

How to find the maximum height of the ball?

(b) To find the maximum height of the ball, we need to find the vertex of the parabola defined by the equation. The x-coordinate of the vertex is given by:

x = -b / (2a)

where a = -1/16 and b = 6. Substituting these values, we get:

x = -6 / (2(-1/16)) = 48

The y-coordinate of the vertex is given by:

[tex]y = -1/16(48)^2 + 6(48) + 3 = 75[/tex]

Therefore, the maximum height of the ball is 75 feet.

How to find the distance of the ball?

(c) To find how far from the child the ball strikes the ground, we need to find the value of x when y = 0 (since the ball will be at ground level when its height is 0).

Substituting y = 0 into the equation, we get:

[tex]0 = -1/16x^2 + 6x + 3[/tex]

Multiplying both sides by -16 to eliminate the fraction, we get:

[tex]x^2 - 96x - 48 = 0[/tex]

Using the quadratic formula, we can solve for x:

[tex]x = [96 \ ^+_- \sqrt{(96^2 - 4(-48))}]/2\\x = [96\ ^+_- \sqrt{(9408)}]/2\\x = 48 \ ^+_- \sqrt{(2352)[/tex]

x ≈ 4.4 or x ≈ 91.6

Since the ball is thrown from x = 0, we can discard the negative solution and conclude that the ball strikes the ground approximately 91.6 feet from the child.

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Find the volume of the rectangular prism.

Answers

Answer:

Step-by-step explanation:

0.7 cubic kilometers

V= lwh

V=(.5)(2)(.7)

find a 95 confidence interval for the mean surgery time for this procedure. round the answers to two decimal places. The 95% confidence interval is _____ , ______

Answers

To find a 95% confidence interval for the mean surgery time for this procedure, you need to use the following formula:

CI = X-bar ± (t * (s / √n))

where:
- CI is the confidence interval
- X-bar is the sample mean
- t is the t-score, which corresponds to the desired confidence level (95%) and the degrees of freedom (n-1)
- s is the sample standard deviation
- n is the sample size

1. Calculate the sample mean (X-bar), sample standard deviation (s), and sample size (n).
2. Find the appropriate t-score using a t-table or calculator for 95% confidence level and (n-1) degrees of freedom.
3. Plug the values into the formula and calculate the interval.
4. Round the answers to two decimal places.

The 95% confidence interval for the mean surgery time is (lower limit, upper limit). Make sure to provide the specific values for your data in the formula.

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complete question:

find a 95 confidence interval for the mean surgery time for this procedure. what quantities do you need to calculate the 95 confidence interval ?

Prove or disprove the identity:
[tex]\frac{(sin(t)+cos(t))^{2} }{sin(t)cos(t)} =2+csc(t)sec(t)[/tex]

Answers

The trigonometric identity [sint + cost]²/sin(t)cos(t) = 2 + csc(t)sec(t).

What are trigonometric identities?

Trigonometric identities are mathematical equations that contain trigonometric ratios.

Since we have the trigonometric identity

[sint + cost]²/sin(t)cos(t) = 2 + csc(t)sec(t). We want to show that the left-hand-side L.H.S = right-hand-side R.H.S. We proceed as folows

Since we have L.H.S = [sint + cost]²/sin(t)cos(t), so expanding the numerator, we have that

[sint + cost]²/sin(t)cos(t), = [sin²t + 2sintcost + cos²(t)]/sin(t)cos(t)

Using the trigonometric identity sin²t + cos²t = 1, we have that

[sin²t + 2sintcost + cos²(t)]/sin(t)cos(t) =  [sin²t + cos²(t) + 2sintcost]/sin(t)cos(t)

=  [1 + 2sintcost]/sin(t)cos(t)

Dividing through by the denominator sin(t)cos(t) , we have that

[1 + 2sintcost]/sin(t)cos(t) = [1/sin(t)cos(t) + [2sintcost]/sin(t)cos(t)

= 1/sin(t) × `1/cos(t) + 2

= cosec(t)sec(t) + 2  [since cosec(t) = 1/sin(t) and sec(t) = 1/cos(t)]

= 2 +  cosec(t)sec(t)

= R.H.S

Since L.H.S = R.H.S

So, the trigonometric identity [sint + cost]²/sin(t)cos(t) = 2 + csc(t)sec(t).

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s there a vector field G on 3 such that curlG =xyz, −y^6z^5, y^5z^6?YesNoExplain.There ---Select--- is is no such G because div(curl G) ? = ≠ 0.

Answers

Expression is not equal to zero, we cannot find a vector field G such that curl G = (xyz, -y⁶z⁵, y⁵z⁶). Therefore, the answer is no.

Describe more about why this answer is no?

There is no such G because the divergence of curl G is not equal to zero. The divergence of curl G is given by the scalar triple product identity:

div(curl G) = dot(grad, curl G)

Using this identity and the given components of curl G, we have:

div(curl G) = x(∂/∂x)(-y⁶z⁵) + y(∂/∂y)(y⁵z⁶) + z(∂/∂z)(xyz)
div(curl G) = -6xy⁵z⁵ + 5y⁶z⁵ + xz

Since this expression is not equal to zero, we cannot find a vector field G such that curl G = (xyz, -y⁶z⁵, y⁵z⁶). Therefore, the answer is no.

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18 square root 10 times square root 2
In radical/ square root form

Answers

4√5 is the simplified form of  square root of 10 times square root of 8 .

First, The square root of ten is √10

and, the square root of 8 is √8

Now, simplify square root of 10 times square root of 8.

= √10×√8

By radical property (√a×√b=√a×b

So,√10×√8=√(10×8)=√80

=√16×5

=4√5

Thus, 4√5 is the simplified form of  square root of 10 times square root of 8 .

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TELL WHETHER THE TRIANGLE IS A RIGHT TRIANGLE

Answers

Answer:

use Pythagorean theorem

Step-by-step explanation:

:)

a^2+b^2=c^2 if equal triangle is right!

Answer:

7. No.  8. Yes.

Step-by-step explanation:

Use the pythagorean theorem.

[tex]a^{2} + b^2 = c^2[/tex]

Where a and b are legs and c is the hypotenuse.

7.

[tex]3^2 + 7^2 \neq \sqrt{57}^2 \\9 + 49 = 58 \neq 57[/tex]

So it isn't a right triangle.

8.

[tex](5\sqrt{5})^2 = 11^2 + 2^2\\(\sqrt{125})^2 = 121 + 4\\125 = 125[/tex]

So this is a right triangle.

why is f not a function from r to r if a) f(x) = 1∕x? b) f(x) = √x? c) f(x) = ±√(x2 1)?

Answers

The function f is not a function from r to r since none of the given functions are functions from r to r due to either being undefined for certain inputs or having multiple outputs for a single input.


a) f(x) = 1/x

f is not a function from R to R because it is undefined when x = 0. For f to be a function from R to R, it must have a defined output for every real number input.

b) f(x) = √x

f is not a function from R to R because the square root is not defined for negative numbers. Thus, it doesn't have an output for negative real number inputs.

c) f(x) = ±√(x² + 1)

f is not a function from R to R because it violates the definition of a function, which states that each input must have exactly one output. In this case, each input x has two outputs: the positive and negative square roots of (x² + 1).

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Louise is buying wallpaper. It costs $7.98 per meter. She needs 150 feet. How much
will the wallpaper cost? Round to the nearest half dollar.

$365.00

$364.00

$364.94

$364.40

Answers

Answer:

$365.00.

Step-by-step explanation:

Let (X,Y) be uniformly distributed on the triangleD with vertices (1,0), (2,0) and (0,1), as in Example 10.19. (a) Find the conditional probability P(X ≤ 1 2|Y =y). You might first deduce the answer from Figure 10.2 and then check your intuition with calculation. (b) Verify the averaging identity for P(X ≤ 1 2). That is, check that P(X ≤ 1 2)=:[infinity] −[infinity] P(X ≤ 1 2|Y =y)fY(y)dy.

Answers

The reason why the same as the first

Find a linear differential operator that annihilates the given function. (Use D for the differential operator.)For,1+6x - 2x^3and,e^-x + 2xe^x - x^2e^x

Answers

The linear differential operator that annihilates [tex]e^{-x} + 2xe^x - x^2e^x is (D - 2)(D - 1)(D + 1).[/tex]

How to find  linear differential operator?

For [tex]1+6x - 2x^3:[/tex]

The first derivative is [tex]6 - 6x^2[/tex], and the second derivative is -12x. Since the second derivative is a constant multiple of the original function, we can use the differential operator D - 2 to annihilate the function:

[tex](D - 2)(1 + 6x - 2x^3) = D(1 + 6x - 2x^3) - 2(1 + 6x - 2x^3)[/tex]

[tex]= (6 - 6x^2) - 2 - 12x + 4x^3 - 2[/tex]

[tex]= 4x^3 - 6x^2 - 12x + 4[/tex]

[tex]For e^{-x} + 2xe^x - x^2e^x:[/tex]

The first derivative is [tex]2e^x - 2xe^x - x^2e^x,[/tex] and the second derivative is [tex]-2e^x + 2xe^x + 2e^x - 2xe^x - 2xe^x - x^2e^x[/tex]. Simplifying, we get:

[tex](D - 2)(D - 1)(D + 1)(e^{-x} + 2xe^x - x^2e^x) = (D - 1)(D + 1)(2e^x - 2xe^x - x^2e^x)[/tex]

[tex]= (D + 1)(2e^x - 4xe^x - 2xe^x + 2x^2e^x - x^2e^x)[/tex]

[tex]= (D + 1)(2e^x - 6xe^x + 2x^2e^x)[/tex]

Therefore, the linear differential operator that annihilates [tex]e^{-x} + 2xe^x - x^2e^x is (D - 2)(D - 1)(D + 1).[/tex]

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Let S be an ellipse in R2 whose area is 11. Compute the area of T(S), where T(x) = Ax and A is the matrix [120-6]

Answers

To compute the area of the transformed ellipse T(S), A transformed ellipse is an ellipse that has been subjected to a transformation, which can change its size, shape, and orientation.

We'll follow these steps:
1. Identify the original ellipse S and its area.
2. Apply the transformation T(x) = Ax.
3. Compute the determinant of matrix A.
4. Compute the area of the transformed ellipse T(S) using the determinant.

Step 1: The original ellipse S has an area of 11.
Step 2: The transformation T(x) = Ax is given by the matrix A = [1 2; 0 -6].
Step 3: Compute the determinant of matrix A.
The determinant is given by det(A) = (1 * -6) - (2 * 0) = -6.
Step 4: Compute the area of the transformed ellipse T(S) using the determinant.
The area of the transformed ellipse T(S) can be computed using the formula:

Area(T(S)) = |det(A)| * Area(S).
Area(T(S)) = |-6| * 11 = 6 * 11 = 66.

The area of the transformed ellipse T(S) is 66.

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Susan went to the supermarket to buy some itemsShe bought 5 pounds of meat at $14 per pound and a packets of sodas at $9 per pack which equation can be used to determine the total amount y that Susan paid A y=9x+70 B y=14x+9
C y=9x-14 D Y=70x+9
PLEASE HELPP

Answers

The equation that can be used to determine the total amount y that Susan paid is [tex]y=14x+9[/tex]. The Option B is correct.

What equation can be used to calculate Susan's total purchase cost?

To calculate the total amount paid by Susan at the supermarket, we need to add the cost of all the items she bought.

From the given information, we know that:

She bought 5 pounds of meat at $14 per pound She bought pack of sodas at $9 per pack.

We can use the equation y = $14x + $9, where y represents the total amount paid by Susan and x represents the pounds of meat which can be multiplied.

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Suppose n is a vector normal to the tangent plane of the surface F(x,y,z) = 0 at a point. How is n related to thegradient of F at that point?Choose the correct answer below..A. The gradient of F is a multiple of nB. The gradient of F is equal to n.C. The gradient of F is orthogonal to nD. The gradient of F is not related to n

Answers

If n is a vector normal to the tangent plane of the surface F(x,y,z) = 0 at a point, then option (C) the gradient of F is orthogonal to n.

The gradient of F at a point (x₀, y₀, z₀) is defined as the vector (∂F/∂x, ∂F/∂y, ∂F/∂z) evaluated at that point. This gradient vector is perpendicular (or orthogonal) to the level surface of F passing through that point.

The tangent plane to the surface F(x, y, z) = 0 at a point (x₀, y₀, z₀) is defined as the plane that touches the surface at that point and is perpendicular to the normal vector at that point.

Thus, if n is a vector normal to the tangent plane of the surface F(x, y, z) = 0 at a point (x₀, y₀, z₀), then n is perpendicular to the tangent plane. Since the gradient vector of F at the point (x₀, y₀, z₀) is perpendicular to the tangent plane, it is also perpendicular to n.

Therefore, the correct answer is (C) The gradient of F is orthogonal to n.

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From the set {22, 14, 12}, use substitution to determine which value of x makes the equation true. 2x = 24

Answers

Answer:

x = 12

Step-by-step explanation:

{22, 14, 12}

2x = 24

2(22) = 44

2(14) = 28

2(12) = 24

Find the limit of the sequence using L'Hôpital's Rule. an = (In(n))^2/Зn (Use symbolic notation and fractions where needed. Enter DNE if the sequence diverges.) lim n->[infinity] an =

Answers

The limit of the sequence an = [(ln(n))²]/(3n) using L'Hôpital's Rule is 0.

We can apply L'Hôpital's Rule to find the limit of the given sequence:

an = [(ln(n))²]/(3n)

Taking the derivative of the numerator and denominator with respect to n:

an = [2 ln(n) * (1/n)] / 3

Simplifying:

an = (2/3) * (ln(n)/n)

Now taking the limit as n approaches infinity:

lim n->∞ an = lim n->∞ (2/3) * (ln(n)/n)

We can again apply L'Hôpital's Rule:

lim n->∞ (2/3) * (ln(n)/n) = lim n->∞ (2/3) * (1/n) = 0

Therefore, the limit of the sequence is 0.

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I NEED HELP ON THIS ASAP!! PLEASE, IT'S DUE TONIGHT!!

Answers

Answer:

6. From speed vs. time graphs, we know that in order to find the distance, we need to look at the area covered. Given the rectangular shape below, we know that it would be A=lw so A=60mph(2.5h).

7. A=60mph(2.5h)= 150 miles.

Given the following exponential function, identify whether the change represents growth or decay, and determine the percentage rate of increase or decrease.
y=7900(1.09)^x

Answers

Answer:

The function represents a growth. The percentage rate is 9%.

Step-by-step explanation:

f(x)= a(1+r)^t

f(x) 7900 (1+.09)^x

Using the above equations, since the rate is greater than 1, that means the function represents growth. And to find the percentage rate, take the .09 and multiply it by 100 to convert it into a percentage.

9x-1=41-5x ,find EF sos please

Answers

The given equation is rearranged to obtain 9x - 1 - (41 - 5x) = 0. By simplifying and solving the equation, we get x = 3.

To solve this equation, we first simplify it by subtracting what is to the right of the equal sign from both sides of the equation. This gives us 9x - 1 - 41 + 5x = 0, which simplifies to 14x - 42 = 0. We then pull out the like factor of 14 to obtain 14(x - 3) = 0.

Next, we use the zero product property to find the values of x that make the equation true. We know that 14 can never equal 0, so we focus on the expression inside the parentheses. Setting x - 3 equal to 0, we get x = 3.

Therefore, the solution to the given equation is x = 3.

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Complete Question:

Simplify 9x-1=41-5x.

Could use some help on this proof. I can't figure it out.Use induction on the size of S to show that if S is a finite set, then |2s| = 2|S|*Note: Here, |S| means the cardinality of S.

Answers

We have shown that |2S| = 2|S| for all finite sets S, by induction on the size of S.

To prove that if S is a finite set, then |2S| = 2|S| using mathematical induction, we need to show that the statement is true for a base case and then show that it holds for all possible cases.Base Case:When S has only one element, say {x}, then the power set of S, 2S, contains two elements: {} and {x}. Hence, |2S| = 2 = 2|S|.Inductive Hypothesis:Assume that for any finite set S of size k, the statement |2S| = 2|S| holds true.Inductive Step:Consider a set S' of size k+1. Let x be any element in S', and let S = S' \ {x} be the set obtained by removing x from S'. By the inductive hypothesis, we know that |2S| = 2|S|.Now consider 2S' = {A : A ⊆ S'} to be the power set of S'. For any set A in 2S', there are two possibilities:A does not contain x, in which case A is a subset of S and there are 2|S| possible choices for A.A contains x, in which case we can write A as A = {x} ∪ B for some subset B of S. There are 2|S| possible choices for B, so there are 2|S| possible choices for A.Therefore, |2S'| = 2|S| + 2|S| = 2(2|S|) = 2|S'|, which completes the induction step.Thus, we have shown that |2S| = 2|S| for all finite sets S, by induction on the size of S.

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show how you can factor n = pq given the quantity (p − 1)(q − 1).

Answers

If we are given the quantity (p-1)(q-1), we can use it to factor n=pq. This is because of the relationship between Euler's totient function and the prime factors of n.

Specifically, if we know (p-1)(q-1), we can calculate the value of Euler's totient function for n as follows:

φ(n) = (p-1)(q-1)

We can then use this value to find the prime factors of n. One way to do this is to use the fact that for any prime factor p of n, we have:

n = p^k * m, where m is not divisible by p.

Then, we can use Euler's totient function to calculate the value of φ(n) as:

φ(n) = (p-1) * p^(k-1) * φ(m)

By substituting the value we calculated earlier for φ(n), we can solve for p and q:

φ(n) = (p-1)(q-1) = pq - (p+q) + 1

Solving for p and q using the quadratic formula gives:

p = (p+q) / 2 + sqrt((p+q)^2 / 4 - n)
q = (p+q) / 2 - sqrt((p+q)^2 / 4 - n)

Therefore, if we are given the quantity (p-1)(q-1), we can use it to calculate the value of Euler's totient function for n, and then use that to find the prime factors p and q of n.

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Arcs and Angle Relationships in circles , help fast pls

Answers

The value of x in the quadrilateral is 4.

We are given that;

Four angles of quadrilateral 5x, 102, 4y-12, 3x+8

Now,

The sum of all interior angles of quadrilateral is 360degree

So, 5x + 102 + 4y-12 + 3x+8 = 360

Also opposite angles are equal

5x= 3x+8

2x=8

x=4

Therefore, by the properties of quadrilateral the answer will be 4.

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What is the difference of the geometric mean and the arithmetic mean of 18 and 128

Answers

Answer:

Step-by-step explanation:

The arithmetic mean of 18 and 128 is (18+128)/2 = 73.

The geometric mean of 18 and 128 is the square root of their product: √(18*128) = √(2304) = 48.

So, the difference between the geometric mean and the arithmetic mean is:

48 - 73 = -25.

Therefore, the difference of the geometric mean and the arithmetic mean of 18 and 128 is -25.

If -ve root of G is taken then
                                  G = -48
and diff of G and A will be  -48 - 73 = -121

The discrete random variable X is the number of students that show up for Professor Smith's office hours on Monday afternoons. The table below shows the probability distribution for X. What is the expected value E(X) for this distribution?A. 1.2B. 1.0C. 1.5D. 2.0

Answers

The required answer is E(X) = 1.4

The expected value E(X) for this distribution can be calculated by multiplying each possible value of X by its probability, and then adding up these products. Using the table provided, we have:

E(X) = (0)(0.2) + (1)(0.3) + (2)(0.4) + (3)(0.1) = 0 + 0.3 + 0.8 + 0.3 = 1.4

Therefore, the closest option to our calculated expected value is option A, 1.2. However, none of the given options match exactly with our calculation.

To find the expected value E(X) of the discrete random variable X, we need the probability distribution table for X. However, the table is not provided in the question. Please provide the table with the probabilities for each possible value of X, and I will be happy to help you calculate the expected value E(X).

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the 2012 National health and nutrition examination survey reports a 95% confidence interval of 99.8 to 102.0 centimeters for the mean waist circumference of adult women in the United State. a) what is captured by the confidence interval? b) Express this confidence interval as a sequence written in the context of this problem c) what is the margin of error for this confidence interval? Express this interval in the format "estimate plus or minus margin of error" d) would a 99% confidence interval based on the same data be larger or smaller? Explain

Answers

The interval would be wider, with more plausible values, and the margin of error would be larger.

What is confidence interval ?

A confidence interval is a statistical range of values that is used to estimate an unknown population parameter, such as the mean or standard deviation of a distribution, based on a sample of data.

a) The confidence interval captures the plausible range of values for the population mean waist circumference of adult women in the United States. More specifically, it is the range of values that is likely to contain the true population mean with 95% confidence.

b) The confidence interval can be expressed as: "We are 95% confident that the true population mean waist circumference of adult women in the United States falls between 99.8 and 102.0 centimeters."

c) The margin of error for this confidence interval can be calculated by taking half the width of the interval. Therefore, the margin of error is (102.0 - 99.8) : 2 = 1.1. Thus, we can express the confidence interval as "The estimate is 100.9 centimeters plus or minus 1.1 centimeters."

d) A 99% confidence interval based on the same data would be larger than the 95% confidence interval. This is because a 99% confidence level requires a wider interval to capture the true population mean with 99% confidence.

Therefore, the interval would be wider, with more plausible values, and the margin of error would be larger.

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Find the angle of elevation of the sun from the ground when a tree that is 15 yard tall casts a shadow of 24 yards long. Round to the nearest degree.
A 38
B 39
C 63
D 32
E 51

Answers

Answer:

Set your calculator to degree mode.

Please draw the figure to confirm my answer.

[tex] \tan( \alpha ) = \frac{15}{24} [/tex]

[tex] \alpha = {tan}^{ - 1} \frac{5}{8} = 32 \: degrees[/tex]

So the angle of elevation is 32°.

D is the correct answer.

Now select points B and C, and move them around. What do you notice about DE as you move B and C? What do you notice about the ratios of the lengths of the intersected segments as you move B and C?

Answers

The thing that I notice about the ratios of the lengths of the intersected segments as you move B and C is that the ratios is altered (changed) as the position of D changes, but the two ratios was one that remain equal to each other.

What is the ratios  about?

If triangle and a line goes through two sides of the triangle, the line cuts the sides into littler line sections. When we choose any point on the line, the lengths of the smallest line fragments it makes will change. But, the proportion between the lengths of the littler line portions will continuously remain the same.

For case, in the event that one of the smaller line segments is twice as long as another, at that point this proportion will continuously be 2:1, no matter where we choose the point on the line.

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if the mpc = 4/5, then the government purchases multiplier is a. 20. b. 5/4. c. 4/5. d. 5.

Answers

If the marginal propensity to consume(mpc) = 4/5 then the government purchases multiplier is 5. Therefore, the answer is (d) 5.

What is the marginal propensity to consume(mpc)?

The marginal propensity to consume (MPC) is the fraction of each additional unit of income that is spent on consumption. In other words, it is the change in consumption that results from a one-unit change in income.

What is a government purchase multiplier?

The government purchases multiplier is a measure of the impact that changes in government purchases of goods and services have on the overall economy. It is the ratio of the change in the equilibrium level of real GDP to the change in government purchases.

According to the given information

The government purchases multiplier (K) is calculated using the formula:

K = 1 / (1 - MPC)

where MPC represents the marginal propensity to consume.

In this case, the MPC is given as 4/5, so we can substitute this value into the formula:

K = 1 / (1 - 4/5)

= 1 / (1/5)

= 5

Therefore, the government puchases multiplier is 5. Therefore, the answer is (d) 5.

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