2. Initially, a pendulum swings through an arc of 18 inches. On each successive swing, the length of the arc is 0.98 of the previous length a. What is the length of the arc of the 10h swing? b. On which swing is the length of the arc first less than 12 inches?

(a) The joint probability mass function of X and Y x1=0 x2=2 x3=4

y1=0 1/8 0 PY(y1)=1/2

y2=1 1/8 1/4 PY(y2)=1/4

y3=2 0 0 PY(y3)=1/4

(b) X and Y are uncorrelated. (c) The random variables X and Y are not independent with each other.

(a) We know that P(X=x2,Y=y1) = 0, since there are no entries in the table where X=x2 and Y=y1. Therefore,

x1=0 x2=2 x3=4

y1=0 1/8 0 PY(y1)=1/2

y2=1 1/8 1/4 PY(y2)=1/4

y3=2 0 0 PY(y3)=1/4

(b) The covariance of X and Y is :

Cov(X,Y) = E[XY] - E[X]E[Y]

where E[XY] is the expected value of the product XY,

E[X] = x1P(X=x1) + x2P(X=x2) + x3P(X=x3) = 0(1/4) + 2(1/2) + 4(1/4) = 2

E[Y] = y1P(Y=y1) + y2P(Y=y2) + y3P(Y=y3) = 0(1/2) + 1(1/4) + 2(1/4) = 1

Now,

E[XY] = x1y1P(X=x1,Y=y1) + x2y1P(X=x2,Y=y1) + x2y2P(X=x2,Y=y2) + x3y2P(X=x3,Y=y2) = 0(1/8) + 2(0) + 2(1/8) + 4(1/4) = 1.5

Therefore,

Cov(X,Y) = E[XY] - E[X]E[Y] = 1.5 - 2(1) = -0.5

Since the covariance is negative, hence X and Y are negatively correlated.

(c) To determine whether X and Y are independent, check whether:

P(X=x,Y=y) = P(X=x)P(Y=y)

for all possible values of x and y.

Using the joint probability mass function we determined in part (a), we can check this condition:

P(X=0,Y=0) = 1/8 ≠ (1/4)(1/2) = P(X=0)P(Y=0)

P(X=2,Y=1) = 1/8 ≠ (1/2)(1/4) = P(X=2)P(Y=1)

P(X=4,Y=2) = 1/4 ≠ (1/4)(1/4) = P(X=4)P(Y=2)

Therefore, X and Y are not independent.

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The two cases weigh 102,100 decigrams together.

First, we need to convert dekagrams to decigrams, since the question asks for the weight in decigrams.

1 dekagram = 10 grams

1 gram = 10 decigrams

Therefore, 1 dekagram = 100 decigrams

Now, let's calculate the weight of the two cases in decigrams:

Weight of tomato cans case = 563 dekagrams x 100 decigrams/dekagram = 56,300 decigrams

Weight of soup cans case = 458 dekagrams x 100 decigrams/dekagram = 45,800 decigrams

The weight of the two cases together is the sum of the two weights:

Total weight = 56,300 decigrams + 45,800 decigrams = 102,100 decigrams

Therefore, the two cases together weigh 102,100 decigrams.

To solve this problem, we need to first convert the weight of the two cases from dekagrams to decigrams so we can add them together.

1 dekagram = 10 grams

1 gram = 10 decigrams

So,

563 dekagrams = 5630 grams

5630 grams = 56300 decigrams

and

458 dekagrams = 4580 grams

4580 grams = 45800 decigrams

Now we can add the weights of the two cases in decigrams:

56300 decigrams + 45800 decigrams = 102,100 decigrams

Therefore, the two cases weigh 102,100 decigrams together.

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The sequence given is {1,1/3,1/5,1/7,1/9,...} and we are asked to find a formula for the general term an of this sequence. Specifically, the nth term in the sequence is the reciprocal of the (2n - 1)th odd number. Thus, the formula for the general term an of the sequence is given by:

an = (-1)^(n+1) / (2n - 1)

This formula can be derived by noting that the signs of the terms alternate between positive and negative, with the first term being positive. Therefore, we introduce a factor of (-1)^(n+1) to account for the sign of each term. Additionally, we observe that the denominator of each term is an odd number of the form 2n - 1, where n is the position of the term in the sequence. Thus, we express the general term as the reciprocal of the denominator with the appropriate sign.

In summary, the formula for the general term an of the sequence {1,1/3,1/5,1/7,1/9,...} is an = (-1)^(n+1) / (2n - 1), where n is the position of the term in the sequence. This formula gives us a way to find any term in the sequence by plugging in its position for n.

To further explain, we can consider the first few terms of the sequence and see how the formula applies. The first term corresponds to n = 1, so we have a1 = (-1)^(1+1) / (2(1) - 1) = 1/1 = 1. The second term corresponds to n = 2, so we have a2 = (-1)^(2+1) / (2(2) - 1) = -1/3. Similarly, the third term corresponds to n = 3, so we have a3 = (-1)^(3+1) / (2(3) - 1) = 1/5. We can continue in this way to find any term in the sequence using the formula for the general term.

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Answer: B

Step-by-step explanation: red to blue

Answer: B

Step-by-step explanation:

Because it asks for you to create a ratio comparing red to blue, you need to order it that way. Since there are 5 reds and 6 blues, you list the 5 in the ratio before you list the 6. It would end up looking like this:

5:6

Answer:

Step-by-step explanation:

If I found the mean, the answer would be:

3+ 4+4+4+5+6+7+23= 56

56/ 8 = 7

If I found the average value using the median, the answer would be 4.5.

In this set of data, the anomaly is 23 as it is much higher than the other numbers.

The median is more accurate because it find the more ‘central’ number and is not affected as greatly with anomalies whereas the mean is affected greatly with anomalies as it raises the value significantly.

Therefore, the median is better to work out the average in this set of data.

:)

Larry can have 5 tanks of goldfish and 3 tanks of minnows, with 5 goldfish and 5 minnows in each tank.

To find out how many goldfish and how many minnows will be in each tank, we need to find the greatest common divisor (GCD) of 25 and 15, which represents the largest number of fish that can be evenly divided into both groups.

The prime factorization of 25 is 55, and the prime factorization of 15 is 35, so the GCD of 25 and 15 is 5.

This means that Larry can put 5 goldfish and 5 minnows in each tank, and he will have:

25 / 5 = 5 tanks of goldfish

15 / 5 = 3 tanks of minnows

So Larry can have 5 tanks of goldfish and 3 tanks of minnows, with 5 goldfish and 5 minnows in each tank.

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Answer:

k<-10

Step-by-step explanation:

-3k+5>35

-3k+5-5>35-5

simplifica la expresión

k<-10

Answer: Answer below in pic

Step-by-step explanation:

:)

Answer:

Exact answer (x = -127/3) or Rounded answer (x = -42.3)

Step-by-step explanation:

First, we will need to find the measure of the third angle in the triangle, which we can call angle y:

The sum of all the angles in a triangle is always 180, so we can find the measure of angle y by subtracting the sum of the two angles we know from 180:

[tex]y+96+31=180\\y+127=180\\y=53[/tex]

Angle y and the angle measuring -3x° are supplementary angles, which means the sum of these two angles is 180°.

We know that they're supplementary because of the straight line that separates them, because straight lines create straight angles which are 180°

Thus, we can find the value of x by making the sum of the -3x° angle and the 53° angle equal to 180° and solve for x:

[tex]-3x+53=180\\-3x=127\\x=-43.333333=-43.3\\x=-127/3[/tex]

-127/3 is the exact answer, while -43.3 is the rounded answer.  Feel free to use any of the two.

The y-intercept of equation 11 + 2t where t is the months after the birth of the baby is 11.

The equation 11 + 2t is modeled by the situation where the weight, in pounds, of a newborn baby after t months is stated.

An equation is represented by y = b + mx where b is the y-intercept and m is the slope of the graph. On comparing the given equation 11 + 2t by the standard equation we have 11 as the intercept and 2 as the slope.

We can interpret from the given context and the equation that the newborn baby is born with 11 pounds weight at birth and with every month there is an increase of 2 pounds in the weight of the newborn.

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If cruz purchased a large pizza for $12.75. It serves 5 people, the cost per serving of the pizza is $2.55. So, correct option is A.

To find the cost per serving of the pizza, we need to divide the total cost of the pizza by the number of servings. In this case, the pizza costs $12.75 and serves 5 people.

Therefore, the cost per serving can be calculated as:

Cost per serving = Total cost of pizza / Number of servings

Cost per serving = $12.75 / 5

Cost per serving = $2.55

So, the cost per serving of the pizza is $2.55.

When working with fractions or dividing quantities, we need to pay attention to the units involved. In this case, the units of the cost and the servings must match for the division to be meaningful.

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The  statement about probability that is true is option The probability of landing on orange is equal to the probability of landing on yellow.

From the  question, the spinner has:

8 sections, with:

So probability of one getting on any section is  = 1/8, or 0.125.

Therefore, the  probability of getting on orange will still be the same as the probability of landing on yellow and as such option C is correct.

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Educational psychology provides teachers with research-based principles to guide their teaching.

When teachers go through educational psychology, they are taught on ways to improve their teaching.

These ways will be based on research overtime that have proved efficient in helping students learn from teachers.

Some of these include empowering school social and cultural structures, minimizing bias, implementing an equity pedagogy, the method of knowledge creation, and integrating content (Banks, 1995a).

The main goal of multicultural education is to reduce barriers to educational opportunity and success for students from different cultural backgrounds. The principle that all pupils, regardless of culture, deserve educational equity serves as its cornerstone.

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You would expect have 5 CDs to be rap in the next 30 CDs

From the question, we have the following parameters that can be used in our computation:

pop 65

rock 10

rap 15

This means that we have the following proportion

Rap = 15/(65 + 10 + 15)

Evaluate

Rap = 15/90

So, we have

Rap = 1/6

Considering loaning 30 CDs out, we have

Rap = 1/6 * 30

Rap = 5

Hence, the expected values of rap CDs is 5

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Since a straightedge lacks measurement gradients, it can only be used to create or draw straight lines—not to measure length.

An instrument for drawing straight lines or ensuring their straightness is a straightedge or straight edge. It is typically referred to as a ruler if its length is marked with uniformly spaced markings. If no markings are present, it is just a straight edge.

Straight lines can be measured and marked with a ruler. A straight edge won't help you measure, but since they are typically more robustly constructed than rulers, they are a better tool for drawing straight lines. Most of the time, rulers can be used as a straight edge.

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The total cost of the online purchase of $200.00 in Dallas, including the 9.75% sales tax is approximately $219.50.

To calculate the total cost, we first need to find the amount of sales tax. We do this by multiplying the cost of the item by the sales tax rate:

$200.00 x 0.0975 = $19.50

Then, we add the sales tax amount to the cost of the item to get the total cost:

$200.00 + $19.50 = $219.50

Therefore, the total cost of the online purchase of $200.00 in Dallas, including the 9.75% sales tax, is $219.50.

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Complete Question:

If the City of Dallas has a 9.75% sales tax on all online purchases, what is the total cost when you buy an item online that costs $200.00?

We can use the recurrence relation for Bessel functions on the terms involving J_(n+2)(x):

x^2J"n(x) = (n^2 - n)J_n(x) - xJ_(n+1)(x) + (n+2)x^2J_n(x) + 2nxJ_(n+2)(x) + (d/dx)^(n-2) [xJ_n(x) +

To prove the given identity, we will start with the following expression:

x^2J_(n+1)(x) = xJ_n(x) + xJ_(n+2)(x) (Recurrence relation for Bessel functions)

Now, let's differentiate both sides of the above equation n times with respect to x:

(d/dx)^n [x^2J_(n+1)(x)] = (d/dx)^n [xJ_n(x)] + (d/dx)^n [xJ_(n+2)(x)]

Using the Leibniz rule for differentiating products, we can expand each term on the right-hand side:

(d/dx)^n [x^2J_(n+1)(x)] = x(d/dx)^n [J_n(x)] + n(d/dx)^(n-1) [J_n(x)] + (d/dx)^(n-2) [J_n(x)] + x(d/dx)^n [J_(n+2)(x)] + 2n(d/dx)^(n-1) [J_(n+2)(x)] + (d/dx)^(n-2) [J_(n+2)(x)]

Now, we can use the recurrence relation for Bessel functions on the terms involving J_n(x) and J_(n+2)(x):

(d/dx)^n [x^2J_(n+1)(x)] = xJ_(n-1)(x) + nJ_(n-1)(x) + (d/dx)^(n-2) [J_n(x)] + xJ_(n+3)(x) + 2nJ_(n+3)(x) + (d/dx)^(n-2) [J_(n+2)(x)]

We can simplify the above expression using the following identity:

(d/dx)^n [xJ_n(x)] = xJ_(n-n)(x) + nJ_(n-1)(x)

Substituting this identity into the above equation, we get:

(d/dx)^n [x^2J_(n+1)(x)] = xJ_n(x) + nJ_n(x) - nJ_(n-1)(x) + xJ_(n+2)(x) + 2nJ_(n+2)(x) + (d/dx)^(n-2) [J_n(x) + J_(n+2)(x)]

Next, we can multiply both sides of this equation by x^2 and simplify using the identity:

(n+1)J_n(x) = xJ_(n+1)(x) + xJ_(n-1)(x)

Multiplying both sides by x and substituting the resulting expression into the previous equation, we obtain:

x^2J"n(x) = (n^2 - n)J_n(x) - xJ_(n+1)(x) + x^2J_(n+2)(x) + 2nxJ_(n+2)(x) + (d/dx)^(n-2) [xJ_n(x) + xJ_(n+2)(x)]

Now, we can use the recurrence relation for Bessel functions on the terms involving J_(n+2)(x):

x^2J"n(x) = (n^2 - n)J_n(x) - xJ_(n+1)(x) + (n+2)x^2J_n(x) + 2nxJ_(n+2)(x) + (d/dx)^(n-2) [xJ_n(x) +

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Answer:

45 2/3, or 45.666666..., rounded to the nearest tenth is 45.7.

The graph of g(x) is a V-shaped graph centered at x = -3, with the vertex at (-3, -2), and opening downward.

We have,

The graph of the function g(x) = -|x+3| - 2 can be obtained by first graphing the function f(x) = |x| and then transforming the graph.

The function f(x) = |x| is a V-shaped graph that passes through the origin and has a slope of 1 on either side of the origin.

The function -|x| is the reflection of f(x) about the x-axis and has the same shape, but opens downwards.

To obtain the graph of g(x) = -|x+3| - 2, we first shift the graph of -|x| three units to the left to get the graph of -|x+3|.

This means that the V-shape of the graph is centered at x = -3.

Then we shift the entire graph downward by 2 units to get the final graph of g(x).

Therefore,

The graph of g(x) is a V-shaped graph centered at x = -3, with the vertex at (-3, -2), and opening downward.

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A table that shows the length and width of at least 3 different rectangles is shown below.

All the rectangles have the same perimeter.

An equation to represent the relationship is x + y = 18.

The independent variable is length and the dependent variable is width.

A graph of the points is shown in the image below.

In Mathematics and Geometry, the perimeter of a rectangle can be calculated by using this mathematical equation (formula);

P = 2(x + y)

Where:

By substituting the given side lengths into the formula for the perimeter of a rectangle, we have the following;

36 = 2(x + y)

18 = x + y

Length       Width     Perimeter

10                   8              36

14                   4              36

15                   3              36

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The probability that a randomly-selected student from this survey ordered Ranch is approximately 0.2383.

We have,

Let R be the event that a student ordered Ranch dressing.

We want to find P(R), the probability that a randomly-selected student from the survey ordered Ranch.

Out of the 3000 students surveyed, 185 never ordered any dressing, so the remaining 3000 - 185 = 2815 students ordered some kind of dressing. Of these, 2100 ordered Caesar but not Ranch, so the remaining

2815 - 2100 = 715 students ordered Ranch or both dressings.

Now,

P(R) is the proportion of students who ordered Ranch or both dressings out of the total number of students surveyed:

P(R) = 715 / 3000 = 0.2383 (rounded to four decimal places)

Thus,

The probability that a randomly-selected student from this survey ordered Ranch is approximately 0.2383.

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A) tan(2θ) = 5/12

B) cos(2θ) = -31

C) tan(θ/2) = ±(6/5)√6 - 3i/5

Given tanθ = -5 and 3x < θ < 5x/2. We need to find:

A) tan(2θ)

B) cos(2θ)

C) tan(θ/2)

First, we can find the value of θ using the given inequality:

3x < θ < 5x/2

Multiplying all terms by 2, we get:

6x < 2θ < 5x

Dividing all terms by 2, we get:

3x < θ < 5x/2

Since we are given that tanθ = -5, we know that θ is in the third quadrant. In the third quadrant, tanθ is negative and sinθ is negative, while cosθ is positive.

Using the Pythagorean identity, we can find the value of cosθ:

[tex]cos^2θ + sin^2θ = 1[/tex]

[tex]cos^2θ + (-5)^2 = 1[/tex]

[tex]cos^2θ = 1 - 25[/tex]

cosθ = √(1 - 25) = √(-24) = 2i√6/6 (taking the positive root since cosθ is positive in the third quadrant)

Now, we can use the double angle identities to find A) and B):

A) tan(2θ) = 2tanθ/(1-tan^2θ)

= 2(-5)/(1-(-5)^2)

= 10/24

= 5/12

B) cos(2θ) = [tex]cos^2θ - sin^2θ[/tex]

= (2i√[tex]6/6)^2[/tex] - (-[tex]5)^2[/tex]

= -6/3 - 25

= -31

Finally, we can use the half-angle identity to find C):

C) tan(θ/2) = ±√((1-cosθ)/1+cosθ))

= ±√((1-2i√6/6)/(1+2i√6/6))

= ±√((1-2i√[tex]6/6)^2[/tex]/(1-24/36))

= ±√((1-2i√6/[tex]6)^2[/tex]/(5/36))

= ±(6/5)√6 - 3i/5

Therefore, the exact values are:

A) tan(2θ) = 5/12

B) cos(2θ) = -31

C) tan(θ/2) = ±(6/5)√6 - 3i/5

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The surface area of a surface parametrized by a function f(s, t), we use the formula:

Surface Area = ∫∫ √[f_s(s,t)^2 + f_t(s,t)^2 + 1] ds dt

The formula above calculates the surface area by integrating the square root of the sum of the squares of the partial derivatives of f with respect to s and t, plus one, over the surface.

Essentially, the formula is finding the magnitude of the gradient of the surface, which gives the rate of change of the surface in all directions.

Surface Area = ∫∫ √[f_s(s,t)^2 + f_t(s,t)^2 + 1] ds dt

The surface area formula can be used to find the surface area of various types of surfaces, such as parametric surfaces, implicit surfaces, and surfaces of revolution.

However, the integration required to evaluate the formula can be quite challenging, especially for complex surfaces. In such cases, numerical methods may be used to approximate the surface area.

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The situation that can use the binomial probability distribution is a sampling of 100 parts to determine whether or not they meet specifications.

The binomial probability distribution is used to model the probability of a certain number of successes in a fixed number of independent trials, where each trial has only two possible outcomes: success or failure. In the given situation, each part in the sample either meets the specifications (success) or does not (failure), which makes it a binomial experiment.

To use the binomial probability distribution, we need to know the probability of success (p) and the number of trials (n). In the given situation, we can determine the probability of a part meet specifications based on the given specifications, and the number of trials is fixed at 100, as we are sampling 100 parts.

Using the binomial probability distribution, we can calculate the probability of a certain number of parts meeting specifications out of the 100 sampled parts. This can be useful in determining whether the sample meets the expected specifications or if there are any issues with the manufacturing process.

In summary, the binomial probability distribution can be used in the given situation of sampling 100 parts to determine whether or not they meet specifications, as it involves a fixed number of independent trials with only two possible outcomes.

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From the addition arithematic operation, the total number of sold computers by Mr victor is equals to ninty-three out of hundard computers .

Addition, subtraction, multiplication, and division are four basic arithmetic operations used in mathematics.

Total number of computers Mr victor has

= 100

Number of computers sold by him in morning = w

Number of computers sold by him in afternoon = 2w + 3

Number of computers left after selling = 7

We have to determine the number of computers he had to sell. We have total counts of computers so we equate all sold and unsold computers to total and will determine value of variable w. Using addition, w + 2w + 3 + 7 = 100

Simplify, 3w + 10 = 100

=> 3w = 90

Dividing by 3 both sides,

=> w = 30

So, Number of computers sold in morning = 30

Number of computers sold in afternoon = 2×30 + 3 = 63

So, total sold computers = 63 + 30 = 93.

Hence, required value is 93.

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The best measure of variability for the data and the player which was more consistent include the following: B. Player B is the most consistent, with a range of 9.

In Mathematics and Statistics, interquartile range (IQR) of a data set and it is typically calculated as the difference between the first quartile (Q₁) and third quartile (Q₃):

Interquartile range (IQR) of Player A = Q₃ - Q₁

Interquartile range (IQR) of Player A = 4 - 1.5

Interquartile range (IQR) of Player A = 2.5.

Range of Player A = Highest number - Lowest number

Range of Player A = 8 - 1

Range of Player A = 7

Interquartile range (IQR) of Player B = Q₃ - Q₁

Interquartile range (IQR) of Player B = 5 - 1.5

Interquartile range (IQR) of Player B = 4.5.

Range of Player B = Highest number - Lowest number

Range of Player B = 10 - 1

Range of Player B = 9

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The length of the missing sides of the two quadrilaterals are listed below:

In this problem we must determine the length of missing sides in two quadrilaterals, this can be done with the help of Pythagorean theorem and properties for special right triangles:

r = √(x² + y²)

45 - 90 - 45 right triangle

r = √2 · x = √2 · y

Where:

Now we proceed to determine the missing sides for each case:

a = √[(6 - 3)² + 4²]

a = √(3² + 4²)

a = √25

a = 5

Case 2

z = √[(22 - 4√2 - 15)² + 4²]

z = √[(7 - 4√2)² + 4²]

z = 4.219

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Using Chebyshev's Inequality, the lower bound for the number of signals that need to be sent so that the total number of errors are within 10% of the expected number of errors with at least 95% probability is 846.

Chebyshev's Inequality states that for any random variable X with finite mean μ and variance σ², the probability that X deviates from μ by more than k standard deviations is at most 1/k².

In other words,

P(|X-μ| ≥ kσ) ≤ 1/k².

In this problem, we know that the number of errors follows a Poisson distribution with a mean of 36 errors, which means that the mean and variance are both 36.

Let X be the total number of errors in n signals. We want to find the smallest value of n such that

P(|X-μn| ≥ 0.1μn) ≤ 0.05,

where μn = nμ is the expected number of errors in n signals.

Using Chebyshev's Inequality, we have

P(|X-μn| ≥ 0.1μn) ≤ σ²/[0.1²μn²] = σ²/[0.01μ²n²] = 1/25,

where σ² = 36 is the variance of X.

Therefore, we need to solve the inequality

1/25 ≤ 0.05,

which implies n ≥ 846. Hence, the lower bound for the number of signals that need to be sent is 846.

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The closest option is (d) 12.054 to 15.946.

To find the confidence interval for the mean of a normal population, we use the formula:

CI = x ± z* (σ/√n)

where x is the sample mean, z* is the critical value from the standard normal distribution corresponding to the desired confidence level (80% in this case), σ is the population standard deviation (unknown), and n is the sample size.

Since the population standard deviation is unknown, we can estimate it using the sample standard deviation:

s = √[ Σ(xi - x)² / (n - 1) ]

where xi is the ith observation, x is the sample mean, and n is the sample size.

Plugging in the values from the sample, we get:

x = (10 + 12 + 18 + 16) / 4 = 14

s = √[ (10-14)² + (12-14)² + (18-14)² + (16-14)² / 3 ] = 2.94

To find the critical value, we look it up from a standard normal distribution table or use a calculator. For an 80% confidence interval, the critical value is approximately 1.282.

Plugging in all the values, we get:

CI = 14 ± 1.282 * (2.94 / √4) = 14 ± 1.4952

Therefore, the 80% confidence interval for the mean is:

CI = (14 - 1.4952, 14 + 1.4952) = (12.5048, 15.4952)

The closest option is (d) 12.054 to 15.946.

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