of six dvd players, two are defective and four are not. if cecil randomly chooses two of these dvd players, without replacement, the probability that the two he chooses are not defective is , what is the value of ??

Answer: Answer is below <3

Step-by-step explanation:

A

B

A

I hope this is correct, I'm sorry if its wrong :(

The equation of this circle with a radius of 4/7 and is centered at (−2.5, −4.4) is (x + 2.5)² + (y + 4.4)² = 49/16.

It is given to us that a circle has a radius of 7/4 units and is centered at (−2.5, −4.4). We need to write an equation of this circle

Therefore, we can say that the standard form of a circle is:

(x - h)² + (y - k)² = r²

where, (h, k) is center and r is radius of the circle.

when we substitute h = -2.5, k = -4.4 and r = 7/4 in the above formula, we get:

= [x-(-2.5)]² + [y-(-4.4)]² = (7/4)²

= (x + 2.5)² + (y + 4.4)² = 49/16

Hence the equation of circle is (x + 2.5)² + (y + 4.4)² = 49/16.

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As a result, we should not be concerned that the sample does not accurately reflect the population.

We can learn more about average, population, and sample.

What is the population?

The entire group of people, items, or objects that we want to draw a conclusion about is known as the population. For example, if we want to learn about the average age of people in the United States, then the entire population is every individual in the United States.

What is a sample?

A smaller group of individuals, objects, or items that are selected from the population is known as a sample. A random sample is a sample in which every individual in the population has an equal chance of being selected for the sample.

What is an average?

A statistic that summarizes the central tendency of a group of numbers is known as an average.

The mean is the most commonly used average in statistics. The mean is calculated by adding up all the numbers in a group and then dividing by the number of numbers in the group. If we want to learn about the average salary of all teachers in the United States, we'd have to sample every teacher. That's not a feasible option. Instead, we take a smaller sample, which should be representative of the population, and then use the information gathered from that sample to make predictions about the population as a whole.

If we assume that the five teachers in the example are a random sample of all teachers in the United States, then we can conclude that the average salary of all teachers in the United States is around $49,000. As a result, we should not be concerned that the sample does not accurately reflect the population.

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Answer: 210

Step-by-step explanation: i learned that today in school

Answer: 7.286

Step-by-step explanation:  To find the average, here is the formula =

Sum of all values in a data set ÷ the number of values = mean (average)

Step 1: We add the sum of the values

We do=

9 + 3 + 10 + 5 + 8 + 8 + 8 = 51

Step 2: We find the number of values

9  3  10  5  8  8  8  

1    2  3   4  5  6   7

So there are 7 values.

Step 3: We divide the sum of values by the number of values

51 ÷ 7 = 7.286

So the answer is 7.285714....

We round it to the nearest 3 decimal places (3 d.p).

This becomes 7.286

Rounding off the value of X to the nearest whole number, we get that approximately 35 people would be expected to have consumed alcoholic beverages among 50 randomly selected 18-20 year-olds.

In exercise 3.25, it was learned that about 69.7% of 18-20 year-olds consumed alcoholic beverages in 2008.

Now, consider a random sample of fifty 18-20 year-olds.

It is required to calculate the number of people who would be expected to have consumed alcoholic beverages.

Let X be the number of people who have consumed alcoholic beverages out of 50 randomly selected 18-20 year-olds.

Let p be the proportion of 18-20 year-olds who consumed alcoholic beverages in 2008.

Therefore, the sample proportion is given as \hat{p}

Hence, p=0.69 \hat{p}=X/50

Now, by the properties of the sample proportion, E(\hat{p})=p

Therefore,

E(\hat{p})=E(X/50)

Thus, p=E(X/50) Or, X=50p

Substituting the value of p, we have

X=50(0.697)=34.85

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There are a total of 7 ways to seat eight people around a table if Alice and Bob won't sit next to each other. This is because the seating arrangement must be a permutation of the seven people not including Alice and Bob.

We can calculate this by taking the factorial of the number of people not including Alice and Bob, which is seven. Since a factorial is the product of an integer and all the integers below it, we can calculate the factorial of seven by multiplying all the integers from one to seven.

This gives us 7=5040, which is the total number of ways to seat eight people around a table if Alice and Bob won't sit next to each other.

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Answer: I am terrible at these kinds of "sit-uating" problems (haha). My idea is that the three people can be situated in (3−1)!

ways and that the rest can be situated in (5−1)!

ways. Then, the ordering of the five people depends on the partitions of 5 into 3 groups:

Step-by-step explanation:

13/52

52 cards in a deck

13 spades

1-9 of spades

king, queen, jack and ace of spades

that makes 13 spades in a deck of cards

The probability of getting at least one spade when drawing cards at random from a deck of cards without replacement is 0.6492 or 0.65 (rounded to two decimal places).

To find the probability of getting at least one spade, we can first find the probability of getting no spades and subtract it from 1.

The probability of getting no spades in the first draw is 39/52 since there are 13 non-spade cards out of 52 cards in the deck. In the second draw, there are 38 non-spade cards out of 51 since one card has been removed from the deck.

Similarly, in the third draw, there are 37 non-spade cards out of 50. Therefore, the probability of getting no spades in three draws is (39/52) x (38/51) x (37/50) = 0.3508 or 0.35 (rounded to two decimal places).

Finally, we can subtract this probability from 1 to get the probability of getting at least one spade: 1 - 0.3508 = 0.6492 or 0.65 (rounded to two decimal places).

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The area of the pie is approximately 113.0 square inches.

The ratio of a circle's circumference to its diameter is denoted by the mathematical constant pi . It is roughly equivalent to 3.14159 and is not repetitive or terminal. As pi is an irrational number, it cannot be written as an exact fraction of two integers and its decimal representation never ends. Pi is used to compute the characteristics of circles, spheres, cylinders, and other curved objects in many branches of mathematics and science, including geometry, trigonometry, calculus, physics, and engineering.

The area of the circle is given as:

A = πr²

Here, diameter = 12, thus radius is 6 inches.

Substituting the values:

area = 3.14 x (6)²

area = 113.04 square inches

Hence, the area of the pie is approximately 113.0 square inches.

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c

Step-by-step explanation:

c because 30 where any marble can be pulled out

The total number of possible outcomes in the sample space for three coin flips is 8.

When a coin is flipped three times, the sample space consists of all possible outcomes that can occur in the experiment. In this case, each coin flip can result in one of two possible outcomes: heads or tails. Therefore, the total number of possible outcomes in the sample space is obtained by multiplying the number of possible outcomes for each individual flip, since each flip is independent of the others.

Thus, the total number of possible outcomes in the sample space for three coin flips is 2 x 2 x 2 = 8. These outcomes include all possible combinations of heads and tails, such as HHH, HHT, HTH, THH, HTT, THT, TTH, and TTT. Each outcome has an equal probability of occurring, assuming the coin is fair and unbiased.

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Question:

How many outcomes are in the sample space if a coin is flipped three times?

the %Cr in the complex is 26.294%.

To determine the % Cr in the chromium-complex Legna synthesized, she massed out a 1.0240 g sample of the Cr complex. She dissolved the sample in a volumetric flask and made 100.0 mL of solution. From the standard curve of Absorbance versus concentration Legna obtained [Cr3+]=0.03933 M. Calculate the %Cr in the complex.

To determine the % Cr in the chromium-complex synthesized by Legna, we can use the following formula:% Cr = (mass of Cr/mass of sample) x 100We have the mass of the sample, which is 1.0240 g. We need to find the mass of Cr in the sample. To do this, we need to find the number of moles of Cr in the solution, and then use the molar mass of Cr to convert this to mass.

The concentration of Cr3+ in the solution is given as 0.03933 M. We know that the complex is made up of Cr and some other ligands, and the concentration of Cr3+ is not the same as the concentration of Cr in the complex. To find the concentration of Cr in the complex, we need to use the formula:[Cr] = [Cr3+] x (1/x), where x is the number of moles of Cr3+ in the complex.

Let's assume that there is one mole of Cr3+ in the complex, then x = 1. If there are n moles of Cr3+ in the complex, then x = n. We can find x by using the formula:x = (mass of sample/Mr of Cr3+) x [Cr3+]/volume of solutionWe know that the mass of the sample is 1.0240 g, and the volume of the solution is 100.0 mL = 0.1000 L. The molar mass of Cr3+ is 52.00 g/mol. Substituting these values into the formula, we get:x = (1.0240/52.00) x 0.03933/0.1000x = 0.000761 moles of Cr3+ in the complex

Now we can use the formula [Cr] = [Cr3+] x (1/x) to find the concentration of Cr in the complex:[Cr] = 0.03933/0.000761[Cr] = 51.69 M

Finally, we can use the formula:% Cr = (mass of Cr/mass of sample) x 100The molar mass of Cr is 52.00 g/mol. The mass of Cr in the complex is 51.69 x 52.00 = 2689.88 g/mol. Substituting this value and the mass of the sample (1.0240 g) into the formula, we get:% Cr = (2689.88/1.0240) x 100% Cr = 262944.53% Cr = 26.294%

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The height of the cone is 13.38 units

A cone is a three-dimensional shape in geometry that narrows smoothly from a flat base (usually circular base) to a point(which forms an axis to the centre of base) called the apex or vertex.

The volume of a cone = 1/3 πr²h

volume = 2016 units³

r = d/2 = 24/2 = 12 units

2016 = 1/3 × 3.14 × 12² h

6048 = 452.16h

h = 6048/452.16

h = 13.38units

therefore the height of the cone is 13.38 units

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The tip of the woman's shadow is moving away from the pole at a rate of 16/3 ft/s when she is 36 ft from the base of the pole.

Let x be the distance of the woman from the pole, and let y be the length of her shadow on the ground. Since the sun's rays are parallel, the triangles formed by the woman, her shadow, and the pole are similar triangles. Therefore, we can use the following proportion:

(woman's height) / (length of woman's shadow) = (height of pole) / (total length of pole's shadow)

Substituting the given values, we get:

5 / y = 15 / (x + y)

Cross-multiplying and simplifying, we get:

3y = 5(x + y)

3y = 5x + 5y

2y = 5x

y = (5/2)x

We can now differentiate both sides of this equation with respect to time t:

dy/dt = (5/2)dx/dt

We want to find dx/dt when x = 36 ft. To do this, we need to find y when x = 36 ft:

y = (5/2)x = (5/2)(36) = 90 ft

Now we can substitute x = 36 ft and y = 90 ft into the differentiated equation:

dy/dt = (5/2)dx/dt

Solving for dx/dt, we get:

dx/dt = (2/5)dy/dt

We know that dy/dt is the rate at which the woman's shadow is changing, which is given by her walking speed of 4 ft/s. Therefore, dy/dt = 4 ft/s. Substituting this value, we get:

dx/dt = (2/5)(4) = 8/5 ft/s

Therefore, the tip of the woman's shadow is moving away from the pole at a rate of 8/5 ft/s, which is equivalent to 1.6 ft/s or 16/3 ft/s.

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The initial number of newts and toads in the pond were in the ratio 3:4, making the total number of organisms in the pond 7x. Solving for x, we get the initial number of toads and newts in the pond as 108 and 81.

Let's assume that the initial number of newts and toads in the pond were 3x and 4x, respectively. Therefore, the total number of organisms in the pond would be 7x.

When 9 more toads entered the pond, the number of toads became 4x + 9, and the ratio of newts to toads changed to 3:5. This means that the number of newts and toads in the pond increased by a factor of 3/2 and 5/4, respectively. We can set up the following equation to solve for x:

3/2n = 4x + 9

5/4n = 4x + 9

Simplifying these equations, we get:

6x + 18 = 5x + 45

x = 27

So, the initial number of toads in the pond was 4x = 108, and the initial number of newts was 3x = 81.

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The probability that the taxi at fault was blue given an eyewitness said it was is approximately 0.436.

To find the probability that the taxi at fault was blue given an eyewitness said it was, we can use Bayes' theorem. Bayes' theorem is expressed as: P(A|B) = (P(B|A) * P(A)) / P(B)

Where:
- P(A|B) is the probability of A given B (the probability the taxi is blue given the eyewitness said it was blue)
- P(B|A) is the probability of B given A (the probability the eyewitness said the taxi was blue given it was actually blue)
- P(A) is the probability of A (the probability the taxi is blue)
- P(B) is the probability of B (the probability the eyewitness said the taxi was blue)

First, let's define our events:
- A: The taxi is blue (Blue Cab), with a probability of 12% (0.12)
- B: The eyewitness said the taxi was blue

Now, we need to find P(B|A) and P(B).

1. P(B|A) = 0.85 (the probability the eyewitness correctly identifies the blue taxi)
2. P(B) can be found using the law of total probability: P(B) = P(B|A) * P(A) + P(B|A') * P(A')
  - A': The taxi is not blue (Green Cab), with a probability of 88% (0.88)
  - P(B|A') = 1 - 0.85 = 0.15 (the probability the eyewitness incorrectly identifies the green taxi as blue)

So, P(B) = 0.85 * 0.12 + 0.15 * 0.88 = 0.102 + 0.132 = 0.234

Now, we can apply Bayes' theorem:

P(A|B) = (P(B|A) * P(A)) / P(B)
P(A|B) = (0.85 * 0.12) / 0.234
P(A|B) ≈ 0.4359

Rounded to three decimal places, the probability that the taxi at fault was blue given an eyewitness said it was is approximately 0.436 or 436/1000 as a reduced fraction.

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The sample space for rolling the game piece is S = {A, B, C, D}

In mathematics, a set is a well-defined collection of distinct objects, which can be anything like numbers, letters, people, or even other sets. A set is usually denoted by curly braces {} enclosing its elements separated by commas. For example, the set of natural numbers less than or equal to 5 can be denoted as {1, 2, 3, 4, 5}.

Sets can also be described by various methods such as by listing its elements, by set-builder notation, or by using a Venn diagram to visualize relationships between sets. A set can have any number of elements, including none (empty set), and can also have infinite number of elements.

Sets can be combined through set operations such as union, intersection, and complement. The union of two sets A and B is a set that contains all the elements that belong to either A or B (or both). The intersection of two sets A and B is a set that contains all the elements that belong to both A and B. The complement of a set A is the set of all elements that are not in A.

The sample space for rolling the game piece can be represented by the set of possible outcomes, which are the labels on the faces of the game piece. Therefore, the sample space is:

S = {A, B, C, D}

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Answer: 196 Joules (J)

Step-by-step explanation:

To calculate the potential energy of the apple, we can use the formula:

Potential Energy = Mass x Gravity x Height

First, let's convert the height from kilometers to meters:

100 km = 100,000 meters

Now, let's convert the mass of the apple from grams to kilograms:

0.2 gram = 0.0002 kilograms

Using these values, we can calculate the potential energy:

Potential Energy = 0.0002 kg x 9.8 m/s^2 x 100,000 m

Potential Energy = 196 Joules (J)

Therefore, the potential energy of the apple is 196 Joules (J).

To find out whether the community studied in Exercise 13 was unusual or not, a t-test should be utilized to determine whether the average loss observed was significantly different from the regional average.

T-test is a statistical test that assesses whether two population means are statistically different from one another. It is often used in hypothesis testing to determine whether there is a significant difference between two means.

A t-test is utilized when the mean of one variable for two groups is compared to the mean of another variable for those same two groups.

The steps to perform a t-test are given below:

Determine the level of significance (alpha).

Determine the degrees of freedom (DF) for the sample.

Determine the critical value of t.

Calculate the t-value.

Compare the calculated t-value with the critical value of t.

Draw a conclusion as to whether there is a significant difference between the two means or not.

A t-test can be performed using the following formula:

t = (X1 - X2) / [s (1 / n1 + 1 / n2)]

Where:

X1 and X2 are the means of the two samples.

s is the pooled standard deviation of the two samples.

n1 and n2 are the sample sizes for the two groups.

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Experiment Random Variable (x)Possible values of the random variable Discrete or Continuous.

a) Take a 20-question examination Number of questions answered correctly Discrete (0, 1, 2, 3, ..., 20)

b. Observe cars arriving at a tollbooth Number of cars arriving at tollbooth for 1 hour Discrete (0, 1, 2, 3, ...)

c. Audit 50 tax returns Number of returns containing errors Discrete (0, 1, 2, 3, ...)

d. Observe an employee’s work Number of nonproductive hours in an eight-hour workday Continuous

e.Weigh a shipment of goods Number of pounds Continuous Random variables are numerical values that are a result of a random experiment. Random variables are generally classified into two categories

Solution:

discrete random variables and continuous random variables

.Discrete random variables

 When a random variable can assume only a countable number of values, it is called a discrete random variable.

Examples: the number of cars passing by a particular point of a highway in a day or the number of customers served by a shop in a day.

Continuous random variables: 

When a random variable can assume any value within a given range or interval, it is called a continuous random variable.

Examples: temperature, the weight of a person, or the height of a person.Tax returns: The random variable is discrete, as it can only take certain values (0, 1, 2, 3, and so on) since the number of tax returns containing errors is an integer.The shipment of goods: The random variable is continuous because it can assume any value between the minimum and maximum weight of the shipment, and the weight of the shipment can be any value.

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Step-by-step explanation:

y=mx+b

let(-4,-1)

x. y

then lets fill it with the formula

-4=-45(-1)+b

-4=45+b

-b=45+4

-b=49

b=-49

Katherine's hike was 4.7 hours long. She spent 1 hour and 42 minutes going uphill, which was 20% of her hike. This means that her entire hike was (1 hour and 42 minutes) / (20%) = 4.7 hours long.

To calculate this, we need to divide the amount of time spent hiking uphill (1 hour and 42 minutes) by the percentage of her hike spent going uphill (20%). 1 hour and 42 minutes is equal to 102 minutes. 102 minutes / 20% = 4.7 hours. Therefore, Katherine's hike was 4.7 hours long.

We can use the following equation to calculate the answer:

Hike time = (uphill time) / (percentage of uphill time)

Hike time = (102 minutes) / (20%) = 4.7 hours

It is important to note that the calculation can also be done using the amount of time spent going downhill as well. The amount of time spent going downhill will equal the total hike time minus the amount of time spent going uphill. In this case, the amount of time spent going downhill would equal 4.7 hours - 1 hour and 42 minutes = 2.28 hours.

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Maggie is 30 years old, and Bobby is 15 years old if in 3 years, Maggie's age will be 50% greater than Bobby's age and years ago when Maggie was 25 years old, Bobby was 10 years old.

Maggie is 15 years older than Bobby. We have to determine Bobby's age.

Let's suppose that Bobby's age is x, so Maggie's age would be x + 15 years.

1) In 3 years, Maggie's age will be 50% greater than Bobby's age.

The age of Maggie in 3 years would be (x + 15) + 3, and the age of Bobby would be x + 3.

According to the problem, Maggie's age in 3 years would be 50% greater than Bobby's age in 3 years.

So, (x + 15) + 3 = (1.5)(x + 3)

Simplifying the above equation, we get

x + 18 = 1.5x + 4

Now, we will solve for

x.x - 1.5x = -14-0.5x = -14x = 28

Therefore, Bobby is 28 years old now.

2) Years ago, when Maggie was 25 years old, Bobby was 10 years old.

Let's assume that x years ago Maggie was 25 years old. Thus, Bobby was 10 years old at that time.

So, x + 25 = (x + 10) + 15x = 15

Therefore, Maggie is 30 years old now. And Bobby is 15 years old now.

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Answer:

a. Multiply the entire first equation by 3 so that the xs will be eliminated when the two equations are added.

b. Multiply the entire first equation by -2 so that the ys will be eliminated when the two equations are added.

c. y = -5; x = -2

Step-by-step explanation:

a. We're able to cancel a variable when the two variables are the same number with opposite signs (e.g., -3 + 3 = 0, -80 + 80 = 0)

If we multiply the entire first equation by 3, we get

[tex]3(-2x-4y=24)\\-6x-12y=72[/tex]

-6x + 6x = 0

b. We can again use the first equation and multiply it by -2 to cancel out the ys:

[tex]-2(-2x-4y=24)\\4x+8y=-48[/tex]

8y - 8y = 0

c. We can first solve for y by first canceling the xs using the process in part a.

[tex]3(-2x-4y=24)\\\\\\-6x-12y=72\\6x-8y=28\\\\-20y=100\\y=-5[/tex]

We can now plug in -5 for y into the first equation to find x:

[tex]-2x-4(-5)=24\\-2x+20=24\\-2x=4\\x=-2[/tex]

In the following question, among the conditions given, the option- a,b and c stand the same ie- The level of measurement is a ratio. The statistic used for the central tendency is the mean or median, whereas d. birth, "is ordinal."

1. Body weight in pounds: The level of measurement is a ratio. The statistic used for the central tendency is mean or median, while for variability, standard deviation or variance can be used.

2. Number of cigarettes smoked in a day: The level of measurement is a ratio. The statistic used for the central tendency is mean or median, while for variability, standard deviation or variance can be used.

3. Ethnicity: The level of measurement is nominal. The statistic used for the central tendency is the mode, while for variability, there is no appropriate statistic.

4. Birth order: The level of measurement is ordinal. The statistic used for the central tendency is median or mode, while for variability, range or interquartile range can be used.

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Explanation:

Most people with a mental illness in the United States receive care at some point in their lives, but most receive insufficient or inappropriate care. In any given year, fewer than one-third of people with a diagnosable mental illness obtain treatment.

However, according to a study, most people in the United States with a mental disorder in any given 12-month period receive treatment during the same time frame.

According to the National Survey on Drug Use and Health (NSDUH), about one in five adults (18.5%) had a mental illness in 2019. It is said that roughly 22.3 million people aged 18 and above received care for a mental health condition in the preceding year.

Treatment may involve medication, therapy, support groups, or a combination of these methods. The majority of people with mental illness may significantly benefit from these treatments.

As per a study, most people in the United States with a mental disorder in any given 12-month period receive treatment during the same time frame. This statement is true.

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Answer:

y=6x-8

Step-by-step explanation:

The slope-intercept form of a line is y = mx + b, where m is the slope and b is the y-intercept. We are given the slope m = 6 and a point on the line (1,-2). We can use point-slope form to find the equation and then simplify it to slope-intercept form.

Point-slope form: y - y1 = m(x - x1)

Substitute the values of m, x1, and y1:

y - (-2) = 6(x - 1)

Simplify the right side:

y + 2 = 6x - 6

Subtract 2 from both sides:

y = 6x - 8

This is the equation of the line in slope-intercept form.

In the following question, among the various parts to solve- a.) the average cost of the promotion is $210, b.) The probability that Grear will refund more than $25 for a tire is 0.159.

a. For each tire sold, the average cost of the promotion is $210. This calculation is based on the fact that the company offers $1 per 100 miles short of 30,000 miles. As a result, the company will refund $210 for each tire that fails to meet the 30,000-mile mark.

b. The probability that Grear will refund more than $25 for a tire is 0.159. This calculation can be carried out using the following steps: First, we need to calculate the number of standard deviations that correspond to a refund of $25 or more:z = (25 - 21) / 3 = 1.33where 21 is the expected value of the refund and 3 is the standard deviation. Next, we can use a normal distribution table to find the probability of a z-score greater than 1.33. Using the table, we get: P(z > 1.33) = 0.0918Therefore, the probability that Grear will refund more than $25 for a tire is 0.0918 or approximately 0.159.

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a. For each tire sold, the average cost of the promotion is $150 ($1 per 100 miles short of 30,000).

b. The probability that grear will refund more than $25 for a tire is 0%.

To calculate the cost of the promotion per tire,

we must first determine the probability that the tire will need to be replaced before reaching 30,000 miles.

Since tire mileage is normally distributed,

we can use the standard normal distribution to calculate this probability.

The z-score for a tire with a lifetime of 30,000 miles is:(30000-36500)/5000 = -1.3

The probability that a tire will need to be replaced before reaching 30,000 miles is the area to the left of this z-score, which can be found using a standard normal distribution table or calculator.

This probability is approximately 0.0968 or 9.68%.

Therefore, the average cost of the promotion per tire is:0.0968 x $150 = $14.52b.

The probability that Grear will refund more than $25 for a tire can be calculated using the same method as in part a. We must first determine the probability that a tire will need to be replaced before reaching 30,000 miles.

The amount of the refund for a tire with a lifetime of less than 30,000 miles is: ($30,000 - lifetime) / 100 x $1

For a refund amount of $25 or more,

we must have:($30,000 - lifetime) / 100 x $1 ≥ $25

This simplifies to: lifetime ≤ $5000/3, or lifetime ≤ 1666.67 miles

The z-score for a tire with a lifetime of 1666.67 miles is:(1666.67-36500)/5000 = -6.6667

The probability that a tire will need to be replaced before reaching 1666.67 miles is the area to the left of this z-score, which can be found using a standard normal distribution table or calculator.

This probability is approximately 0.0000 or 0%.

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Answer:

1/3 y

Step-by-step explanation:

0,6x