suppose that 8 rooks are randomly placed on a chessboard. what is the probability that none of the rooks can capture any of the others

i: 1

ii: 6

iii: 3

iv: 2

v: 4.5

vi: 2.5

The 90% confidence interval for the given sample is (7.58, 8.60).

To calculate the 90% confidence interval for the given sample assuming normality of the data, we need to use the formula as follows;Confidence interval = X ± Z α/2(σ/√n)Where, X is the sample meanZ α/2 is the Z-score for the desired level of confidenceσ is the population standard deviationn is the sample sizeFirst, we need to calculate the sample mean and standard deviation.Sample mean,

X= (7.9 + 8.3 + 8.4 + 9.6 + 7.7 + 8.1 + 6.8 + 7.5 + 8.6 + 8 + 7.8 + 7.4 + 8.4 + 8.9 + 8.5 + 9.4 + 6.9 + 7.7) / 18

= 8.09

Sample standard deviation,

σ = √[Σ(xi - X)² / (n - 1)]σ = √[(7.9 - 8.09)² + (8.3 - 8.09)² + (8.4 - 8.09)² + (9.6 - 8.09)² + (7.7 - 8.09)² + (8.1 - 8.09)² + (6.8 - 8.09)² + (7.5 - 8.09)² + (8.6 - 8.09)² + (8 - 8.09)² + (7.8 - 8.09)² + (7.4 - 8.09)² + (8.4 - 8.09)² + (8.9 - 8.09)² + (8.5 - 8.09)² + (9.4 - 8.09)² + (6.9 - 8.09)² + (7.7 - 8.09)² / (18 - 1)]σ = 0.761

Now, we need to find the Z α/2 value from the standard normal distribution table.

Z α/2 = 1.645 (for 90% confidence level)Putting the values in the formula,Confidence interval =

X ± Z α/2(σ/√n)

= 8.09 ± 1.645(0.761/√18)

= 8.09 ± 0.511

= (8.09 - 0.511, 8.09 + 0.511)

= (7.58, 8.60).

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Answer:

Step-by-step explanation:

Means of means = means of extremes 8y = x

x = 8y

Option B is the correct answer

Answer:

x=-1

Step-by-step explanation:

Hello there!

The information we are given:

We are told that the distance from point a to c is x + 10

We are told that the distance from a to b is 5

we are also told that the distance from b to c is 2x+6

Because from point A to B and B to C is inside the total of A to C we can add the two together and create a equation to solve for x

so the sum of the two parts 5 + 2x + 6

*combine like terms*

11 + 2x

is equal to the total distance (x+10)

now we solve for x

11 + 2x = x + 10

step 1 subtract x from each side by

2x - x =  x

x -x cancels out

now we have 11 + x = 10

step 2 subtract 11 from each side

11-11 cancels out

10 - 11 = -1

we're left with x = -1

Now lets plug in x and see if A to C is equal to A to B + B to C

(-1) + 10 = 5 + 2(-1) + 6

10 - 1= 9

2*-1=-2

6-2=4

4+5=9

9=9

which is true so we can conclude that x = -1

The approximate interest rate needed to turn $3,500 into $7,000 over 10 years is 9%. Correct answer is C.

The value of money increases over time with the help of compounding interest. If one puts in a principal amount in an account, the amount will increase over time as interest accrues. Let's use the future value formula for the calculation. Let’s assume that the interest rate needed to turn $3,500 into $7,000 over 10 years is x percent. P = $3,500 (principal)FV = $7,000 (future value)

N = 10 years (duration of the investment)Using the future value formula:

FV = P(1 + r/n)^(nt)where, r is the annual interest rate, n is the number of times the interest is compounded in a year, and t is the duration of the investment in years.

Substituting the given values, we have: $7,000 = $3,500(1 + x/n)^(n × 10)We can solve for x by approximating the interest rate using each of the answer options given in the question until we find an answer that is close to $7,000. A calculator can also be used to calculate the compound interest for each option. If the interest rate is 7%, then the interest is compounded annually. Therefore, n = 1$7,000

= $3,500(1 + 0.07/1)^(1 × 10) If the interest rate is 10%, then the interest is compounded annually.

Therefore, n = 1$7,000 = $3,500(1 + 0.1/1)^(1 × 10)Thus, x ≈ 9.57%, greater than the required amount.

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Answer:

Radius is the diameter divided by 2

Answer:

For game ideas, try to make a game that everyone will want to play. Make it fun, challenging, but still beatable, but not too easy. One thing you could do is a trivia game! With lots of different subjects so people can choose what they get questions about. Also, do a lot of research to get the questions! Hope this helped :)

Step-by-step explanation:

Answer:

KING OF QUESTIONS!!!

Step-by-step explanation:

Each player starts out with 10 tokens ( tokens can be anything I recommend spare change or coins. ) the tokens will be used as point tallies at the end of the game.  But to determine who goes first the question master asks a question from the starting deck( The easiest questions) and starting with player one the players answer and whoever answers with the correct answer will go first, the other players will form an orderly line from closest to the correct answer to farthest. ( If there are more than 1 successful answers you pull another card from the next deck. This is an increase in difficulty. And it will keep increasing until there is one person with the correct or closest answer or until they reach the end of the final deck. Remember that this event is highly unlikely) After this is done the game begins.  The question master asks a question the players will answer. The players that get it correct will receive 2 token. The players that do not but are close get 1 and the player to get the farthest from the correct answer loses 1 token. ( Tokens are worth 1 point.)

Roles:

Player 1 ( Answers the questions.)

Player 2 ( Answers the questions.)

Player 3 ( Answers the questions.)

Player 4 ( Answers the questions.)

Question Master & Token Master ( Asks the questions and gives the token to the correct answer. )

How to Win:

Quick Match- Play until a player reaches 30 tokens.

Long Match- Play until all but one player is eliminated.

Ways to Lose-  If a player loses all of there tokens or is cheating they are eliminated, this happens only when the player is caught cheating or stealing tokens from other players or when the player loses all of these tokens due to incorrect answers.

Answer:

√194 or 13.9

Step-by-step explanation:

√(x2 - x1)² + (y2 - y1)²

√[-2 - (-7)² + [4 - (-9)]

√(5)² + (13)²

√25 + 169

√194

= 13.9

Answer:

Buddy this might not be the correct answer but I got either 98 or 418 inches. Don't quote me on it though.

Step-by-step explanation:

Answer:

The part of the bridge that opens is 50 ft.

Step-by-step explanation:

The given parameters of the drawbridge are;

The entire length of the bridge = 100 feet

The height of the isosceles trapezoid formed = 25 feet

The angle at which the drawbridge meets the land ≈ 60°

Therefore, the part of the bridge that opens = The top narrow parallel side of the isosceles trapezoid

The length of each half of the bridge = (The entire length)/2 = 100 ft./2 = 50 ft.

Let 'x' represent the path of the waterway still partly blocked by each half of the bridge inclined

∴ x = 50 × cos(60°) = 25

x = 25 ft.

The path covered by both sides of the drawbridge = 2·x = 2 × 25 ft. = 50 ft.

The part of the bridge that opens = The entire length - 2·x

∴ The part of the bridge that opens = 100 ft. - 50 ft. = 50 ft.

The part of the bridge that opens = 50 ft.

Answer:

28.26

Step-by-step explanation:

6 divided by 2 = 3^2 = 9 x 3.14 = 28.26

Answer: p+(-q)

Step-by-step explanation:

Answer:

The area of the parallelogram is 20cm²

Answer:

A = 20 cm²

Step-by-step explanation:

The area (A) of a parallelogram is calculated as

A = bh ( b is the base and h the height ) , then

A = 5 × 4 = 20 cm²

Answer:

c = 1

Step-by-step explanation:

we have -1/6 + 7/6

since 6 is a common denominator we can do

[tex]\frac{-1}{6} +\frac{7}{6} = c\\\frac{-1+7}{6} = c\\\frac{6}{6} = c\\1 = c\\c = 1[/tex]

Answer:

a) 55°

b) 125°

c) 55°

d) 55°

Step-by-step explanation:

a) 180-(90+35) = 55

b) this angle forms a straight angle with ∡a

c) this angle is vertical, and congruent, with ∡a

d) 180-(70+55) = 55

Answer:73 ft

Step-by-step explanation:

Answer:

(120 + 12.5pi) ft^2

Step-by-step explanation:

10ft x 12 ft = 120ft^2

10ft/2 = 5 ft (Radius)

Area of semi circle:

[tex]\frac{\pi r^{2} }{2} = \frac{\pi 5^{2} }{2} = 12.5\pi ft^{2}[/tex]

Area = (120 + 12.5pi) ft^2

Answer:

4 right angles

Step-by-step explanation:

a straight light intersects  another straight line= creating 4 right angles

The solution to the recurrence relation an = 3an-1 + 4an-2 with initial values ao = 2 and a₁ = 3 is given byan = (-1)4ⁿ - 4(4)ⁿ-¹/16

Given recurrence relation is an = 3an-1 + 4an-2, with initial values ao = 2 and a₁ = 3.

The characteristic equation of the recurrence relation is given byr² - 3r - 4 = 0

Solving the characteristic equation, we get

r² - 4r + r - 4 = 0

r(r - 4) + 1(r - 4) = 0

(r - 4)(r + 1) = 0

r1 = 4, r2 = -1

So, the general solution of the recurrence relation is given by

an = Ar¹ + Br²

For r1 = 4, a4 = 3

a3 + 4a2a4 = 3a3 + 4a2 = 3(4a2 + 4a1) + 4a2= 16a2 + 12a1 ....(1)

For r2 = -1, aₙ₊₁ = 3an + 4an-1aₙ₊₁ = 3an + 4an-1 = 3(A(-1)^n + B(4)^n) + 4(A(-1)^(n-1) + B(4)^(n-1))= 3A(-1)^n - 4A(-1)^(n-1) + 12B(4)^n + 4B(4)^(n-1)= A(-1)^n + 4B(4)^n ....(2)

Putting n = 0 in (2), we get

a1 = A - 4A = -3A = 3 => A = -1

Substituting A = -1 in (1), we get

a4 = 16a2 + 12a1=> a4 = 16a2 + 12(2) => a4 = 16a2 + 24a4 = 16a2 + 24 => a2 = (a4 - 24)/16

Thus the solution to the recurrence relation an = 3an-1 + 4an-2 with initial values ao = 2 and a₁ = 3 is given by

an = (-1)4ⁿ - 4(4)ⁿ-¹/16

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Answer:

250/5 =50 miles per hour

Answer:

y = 1.50x + 4 ;

Step-by-step explanation:

Given that bike rental cost $4 plus $1.50 per hour

From the information given, the change in y per unit change in x is the value of the slope ;

Therefore, Given that total cost = y and x) number of hours

Change in cost per change in number of hours) 1.50 = slope ; intercept = constant = $4

The equation, in slope intercept form :

y = mx + c

y = 1.50x + 4

Two ordinary dice are thrown simultaneously. Determine the number of throws necessary to obtain at least once with probability 0.49 at least once the pair (6,6).

Solution: The probability of getting a pair of 6s in a single throw is 1/36.The probability of not getting a pair of 6s in a single throw is 1 - 1/36 = 35/36.

The probability of not getting a pair of 6s in n throws is (35/36)^n.

The probability of getting a pair of 6s in n throws is 1 - (35/36)^n.

So, for at least one pair of 6s with probability 0.49 in n throws, we have:

1 - (35/36)^n = 0.49⇒ (35/36)^n = 0.51⇒ n ln (35/36) = ln 0.51⇒ n = ln 0.51/ln (35/36) = 72.5 ~ 73So, at least 73 throws are necessary to obtain at least once with probability 0.49 at least once the pair (6,6).

Answer: At least 73 throws are necessary to obtain at least once with probability 0.49 at least once the pair (6,6).

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A. The mean ÿ(t) = 0 and the autocorrelation Ry(t + 7, t) = 4e⁻⁷. Y(t) is wide-sense stationary.

B. the cross-correlation Rxy(t + 7, t) = 2e⁻⁷. X and Y are jointly wide-sense stationary.

C. The autocovariance Cy(t + 7, t) = 4e⁻⁷. Y(t) is not a white process because autocovariance Cy(t + 7, t) is not a Dirac delta function.

To find the mean ÿ(t) = E[Y(t)] and the autocorrelation Ry(t + 7, t) = E[Y(t + 7)Y(t)], we substitute the expression for Y(t) into the formulas:

(a) Mean of Y(t):

ÿ(t) = E[Y(t)] = E[2X(t) + sin(2t)]

= 2E[X(t)] + E[sin(2t)]

= 2(0) + 0

= 0

(b) Autocorrelation of Y(t + 7, t):

Ry(t + 7, t) = E[Y(t + 7)Y(t)]

= E[(2X(t + 7) + sin(2(t + 7)))(2X(t) + sin(2t))]

Expanding the expression:

Ry(t + 7, t) = E[4X(t + 7)X(t) + 2X(t + 7)sin(2t) + 2sin(2(t + 7))X(t) + sin(2(t + 7))sin(2t)]

Since X(t) is a WSS random process with mean 0, its autocorrelation Rx(T) = E[X(t + 7)X(t)] = e^(-|7|).

Using the properties of expectation and the independence of X(t) and sin(2t):

Ry(t + 7, t) = 4E[X(t + 7)X(t)] + 2E[X(t + 7)]E[sin(2t)] + 2E[sin(2(t + 7))]E[X(t)] + E[sin(2(t + 7))]E[sin(2t)]

= 4Rx(7) + 2(0)(0) + 2(0)(0) + 0

= 4e⁻⁷

Therefore, the mean ÿ(t) = 0 and the autocorrelation Ry(t + 7, t) = 4e⁻⁷.

To determine if Y(t) is wide-sense stationary, we need to check if the mean and autocorrelation are independent of time:

Mean: The mean ÿ(t) is constant and does not depend on time t. Thus, Y(t) has a constant mean.

Autocorrelation: The autocorrelation Ry(t + 7, t) depends only on the time difference of 7. It is independent of the absolute values of t. Therefore, Y(t) has a stationary autocorrelation.

Since Y(t) has a constant mean and a stationary autocorrelation, it is wide-sense stationary.

Moving on to part (b), we need to find the cross-correlation Rxy(t + 7, t) = E[X(t + 7)Y(t)].

Rxy(t + 7, t) = E[X(t + 7)Y(t)]

= E[X(t + 7)(2X(t) + sin(2t))]

Expanding the expression:

Rxy(t + 7, t) = E[2X(t + 7)X(t) + X(t + 7)sin(2t)]

Since X(t) is a WSS random process, its autocorrelation Rx(T) = e|⁻⁷|.

Using the properties of expectation and the independence of X(t) and sin(2t):

Rxy(t + 7, t) = 2E[X(t + 7)X(t)] + E[X(t + 7)]E[sin

(2t)]

= 2Rx(7) + 0

= 2e⁻⁷

Therefore, the cross-correlation Rxy(t + 7, t) = 2e⁻⁷.

To determine if X and Y are jointly wide-sense stationary, we need to check if the cross-correlation Rxy(t + 7, t) is independent of time:

Cross-correlation: The cross-correlation Rxy(t + 7, t) depends only on the time difference of 7. It is independent of the absolute values of t. Therefore, X and Y have a stationary cross-correlation.

Since the cross-correlation is stationary, X and Y are jointly wide-sense stationary.

Moving on to part (c), we need to find the autocovariance Cy(t + 7, t) = E[(Y(t + 7) - ÿ(t + 7))(Y(t) - ÿ(t))].

Expanding the expression:

Cy(t + 7, t) = E[(2X(t + 7) + sin(2(t + 7))) - 0][(2X(t) + sin(2t)) - 0]

= E[(2X(t + 7) + sin(2(t + 7)))(2X(t) + sin(2t))]

Using the same approach as in part (b), we expand the expression and evaluate the expectation:

Cy(t + 7, t) = 4E[X(t + 7)X(t)] + 2E[X(t + 7)]E[sin(2t)] + 2E[sin(2(t + 7))]E[X(t)] + E[sin(2(t + 7))]E[sin(2t)]

= 4Rx(7) + 0 + 0 + 0

= 4e⁻⁷

Therefore, the autocovariance Cy(t + 7, t) = 4e⁻⁷.

To determine if Y(t) is white, we check if the autocovariance Cy(t + 7, t) is a Dirac delta function. Since Cy(t + 7, t) = 4e⁻⁷ ≠ 0, it is not a Dirac delta function. Hence, Y(t) is not a white process.

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(a) The ordinary differential equation is given by y(t) + y(t) + 3y(t) = 0. Using Laplace transform, we have(L [y(t)] + L [y(t)] + 3L [y(t)]) = 0L [y(t)] (s + 1) + L [y(t)] (s + 1) + 3L [y(t)] = 0L [y(t)] (s + 1) = - 3L [y(t)]L [y(t)] = - 3L [y(t)] /(s + 1)Taking the inverse Laplace of both sides, we have y(t) = L -1 [- 3L [y(t)] /(s + 1)]y(t) = - 3L -1 [L [y(t)] /(s + 1)]

On comparison, we get y(t) = 3e^{-t} - 2e^{-3t}.The initial conditions are y(0) = 1 and y(0) = 2 respectively.(b) The ordinary differential equation is given by y(t) - 2y(t) + 4y(t) = 0. Using Laplace transform, we have L [y(t)] - 2L [y(t)] + 4L [y(t)] = 0L [y(t)] = 0/(s - 2) + (- 4)/(s - 2)

Taking the inverse Laplace of both sides, we have y(t) = L -1 [0/(s - 2) - 4/(s - 2)]y(t) = 4e^{2t}.The initial conditions are y(0) = 1 and y(0) = 2 respectively.(c) The ordinary differential equation is given by y(t) + y(t) = sint. Using Laplace transform, we have L [y(t)] + L [y(t)] = L [sint]L [y(t)] = L [sint]/(s + 1)

Taking the inverse Laplace of both sides, we have y(t) = L -1 [L [sint]/(s + 1)]y(t) = sin(t) - e^{-t}.The initial conditions are y(0) = 1 and y(0) = 2 respectively.(d) The ordinary differential equation is given by y(t) + 3y(t) = sint. Using Laplace transform, we have L [y(t)] + 3L [y(t)] = L [sint]L [y(t)] = L [sint]/(s + 3)Taking the inverse Laplace of both sides, we have y(t) = L -1 [L [sint]/(s + 3)]y(t) = (1/10)(sin(t) - 3cos(t)) - (1/10)e^{-3t}.

The initial conditions are y(0) = 1 and y(0) = 2 respectively.(e) The ordinary differential equation is given by y(t) + 2y(t) = e^{t}. Using Laplace transform, we have L [y(t)] + 2L [y(t)] = L [e^{t}]L [y(t)] = 1/(s + 2)Taking the inverse Laplace of both sides, we havey(t) = L -1 [1/(s + 2)]y(t) = e^{-2t}The initial conditions are y(0) = 1 and y(0) = 2 respectively.

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Answer:

d is parallel to e

Step-by-step explanation:

Since b is parallel to e and d is perpendicular to b , then

d is perpendicular to e

Answer:

Surface area of cuboid = 78 unit²

Step-by-step explanation:

Given diagram is a cuboid prism

Given:

Length of cuboid = 5 unit

Width of cuboid = 3 unit

Height of cuboid = 3 unit

Find:

Surface area of cuboid

Computation:

Surface area of cuboid = 2[lb + bh + hl]

Surface area of cuboid = 2[(5)(3) + (3)(3) + (3)(5)]

Surface area of cuboid = 2[15 + 9 + 15]

Surface area of cuboid = 2[39]

Surface area of cuboid = 78 unit²

Answer:

B. 0

Step-by-step explanation:

There aren't enough sides for you to roll a nine

Answer:

230

Step-by-step explanation:230

Answer: 3 times greater

Step-by-step explanation:

Height: 4x3=12

Length: 3x3=9

Width: 3x3=9

The sides on the red cuboid times by 3 equals the sides on the purple one.

Hope this helps :)