Two similar solids have a scale factor of 4:3
.

What is the ratio of their volumes expressed in lowest terms?



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:

The age of Layla who youngest of four siblings is 18 years old

The age of 4 sibling are in consecutive even integers

Age of 1st sibling = x

Age of 2nd sibling = x + 2

Age of 3rd sibling = x + 4

Age of 4th sibling = x + 6

Sum of the sibling age = 84

x + x + 2 + x + 4 + x + 6 =84

4x + 12 = 84

4x = 84 -12

4x = 72

x = 18

Layla is youngest  sibling hence her age will be 18 years

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The question is incorrect the correct question is :

Layla is the youngest of four siblings whose ages are consecutive even integers. If the sum of their ages is 84, find Layla's age

Answer: 3.743324

Step-by-step explanation:

The average rate of change for % of drivers in an accident between 20 -  100 practice hrs is [tex]-0.2[/tex].

To find the average rate, we will to calculate the slope of the line passing through the points (20, 20%) and (100, 4%).

Using the formula for slope, we get:

Slope = (4% - 20%) / (100 - 20)

Slope = -16% / 80

Slope = -0.2

The average rate of change for the percent of drivers in an accident from states that require between 20 and 100 practice hours is -0.2 which means that for every additional 10 practice hours required by a state, the percent of drivers in an accident decreases by an average of 2%.

Missing table:

Practice hours 20 40 60 80 100

Percent of drivers 20% 19% 18% 10% 4%

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The direction of conventional current flow is opposite to the direction of electron flow. Therefore, to determine the direction of conventional current, we need to know the direction of electron flow in a given situation.

Electrons, which are negatively charged particles, flow from the negative terminal of a battery to the positive terminal, while conventional current flows from the positive terminal to the negative terminal.

In the absence of any further information or context, it is impossible to determine a situation that would result in a conventional electric current that flows northward. The direction of electron flow and, therefore, the direction of conventional current flow, depends on the specific configuration of the electrical circuit.

That being said, it's important to note that conventional current flow is just a conventional convention, and its direction is not fundamental to the operation of electrical circuits. Regardless of the direction of conventional current flow, the actual flow of electrons and the operation of the circuit will be the same.

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The boat is either about 2.334 miles or 2.666 miles from lighthouse B, depending on whether it sailed to the left or to the right of the line AB.

Let's draw a diagram to help visualize the problem. Let A and B be the positions of the lighthouses, and let C be the position of the boat after sailing 5 miles from A. Let x be the distance from C to B that we want to find, and let θ be the angle ACB.

Since the bearing of the boat from B is N65°E, we know that the angle ACB is (180° - 65°) = 115°. Also, since ACB is a straight line, we have

cos(115°) = x/8

Solving for x, we get

x = 8 cos(115°) ≈ 2.334 miles

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Answer: 4

Step-by-step explanation:

To determine if the means of the weights of the hard body type and soft body type upright vacuum cleaners are different, a two-sample t-test can be conducted.

However, before conducting the test, it must be checked if the assumptions are met. The variables are assumed to be normally distributed and the variances are assumed to be unequal.
Assuming that the sample sizes are large enough (at least 30), a two-sample t-test with unequal variances can be used. The null hypothesis is that the means of the weights of the two types of vacuum cleaners are equal, while the alternative hypothesis is that they are different.
The t-test calculates a t-statistic, which measures the difference between the sample means in terms of the standard error. The higher the t-value, the more likely it is that the means are different. If the calculated t-value exceeds the critical value at the chosen level of significance (usually 0.05), the null hypothesis is rejected.
In conclusion, to determine if the means of the weights of the hard body type and soft body type upright vacuum cleaners are different, a two-sample t-test can be conducted. The assumptions of normality and unequal variances should be checked before conducting the test.

To determine if the means of the weights of hard body and soft body upright vacuum cleaners are different, we need to conduct a hypothesis test. Since the variances are unequal, we'll use the Welch's t-test. Here are the steps:
1. State the null hypothesis (H0) and the alternative hypothesis (H1):
  H0: The means of the weights of hard body and soft body upright vacuum cleaners are equal.
  H1: The means of the weights of hard body and soft body upright vacuum cleaners are different.
2. Calculate the t-value and degrees of freedom using the provided sample data of weights in pounds for both hard body and soft body vacuum cleaners. Make sure to use the formula for Welch's t-test, which accounts for unequal variances.
3. Determine the critical t-value for the desired significance level (e.g., 0.05) and the calculated degrees of freedom from Step 2.
4. Compare the calculated t-value with the critical t-value. If the calculated t-value is greater than the critical t-value, reject the null hypothesis in favor of the alternative hypothesis.
In conclusion, by following these steps and using the sample data of weights in pounds for hard body and soft body upright vacuum cleaners, you can determine if there's enough evidence to conclude that the means of the weights are different.

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Answer:

Step-by-step explanation:

To match each term to the corresponding probability of it snowing tomorrow, we can use the following definitions:

Likely means that the event has a high chance of happening, so the probability is close to 1. For example, P(snow) = 0.9 means that it is very likely to snow tomorrow.

Unlikely means that the event has a low chance of happening, so the probability is close to 0. For example, P(snow) = 0.1 means that it is very unlikely to snow tomorrow.

Certain means that the event will definitely happen, so the probability is exactly 1. For example, P(snow) = 1 means that it will surely snow tomorrow.

Impossible means that the event will never happen, so the probability is exactly 0. For example, P(snow) = 0 means that it will not snow tomorrow at all.

Using these definitions, we can match each term to the corresponding probability as follows:

Likely: P(snow) > 0.5

Unlikely: P(snow) < 0.5

Certain: P(snow) = 1

Impossible: P(snow) = 0

To calculate the standard deviation of a set of data, you need to have the individual data values. The individual data values are the numeric values that make up the data set.

To calculate the standard deviation, you need to perform the following steps:

Calculate the mean (average) of the data set.

For each data value, subtract the mean from the data value.

Square each of the differences calculated in step 2.

Sum the squared differences calculated in step 3.

Divide the sum of the squared differences by the number of data values minus 1 (this is called the "sample" standard deviation) or by the total number of data values (this is called the "population" standard deviation).

Take the square root of the result obtained in step 5 to obtain the standard deviation.

When calculating the standard deviation, it's important to use the correct number of decimal places and units of measurement to ensure accuracy.

What is the definition of accuracy?

Accuracy refers to how close a measured or calculated value is to the true or accepted value.

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Answer:

-4/15

Step-by-step explanation:

Using the formula for slope of a line

m = ( y2-y1)/(x2-x1)

    = ( 14-10) / ( -7-8)

   = 4 / -15

  = -4/15

Answer:

-0.26667

Step-by-step explanation:

(y1 - y2)/(x1 - x2)

(14 - 10)/(-7 - 8)

4 / -15

-0.26667

The answer  is that we can use a hypothesis test to determine if the mean benzene concentration is less in treated water than in untreated water.

: We will use the following hypotheses:

H0: μtreated ≥ μuntreated
Ha: μtreated < μuntreated

where μtreated is the true mean benzene concentration for treated water, and μuntreated is the true mean benzene concentration for untreated water.

We will use a one-tailed t-test with a level of significance of α = 0.05.

Using the Ti-84 Plus calculator, we can find the t-test statistic and p-value. First, we calculate the pooled standard deviation:

Sp =√((n1-1)*s1² + (n2-1)*s2²)/(n1+n2-2))
Sp = √(((5-1)*0.7² + (7-1)*0.6²)/(5+7-2))
Sp = 0.642

Next, we calculate the t-test statistic:

t = (x1 - x2) / (Sp * √(1/n1 + 1/n2))
t = (0.5 - 0.8) / (0.642 *√(1/5 + 1/7))
t = -2.13

Finally, we calculate the p-value:

p-value = tcdf(-100, t, df)
p-value = tcdf(-100, -2.13, 10)
p-value = 0.026

Since the p-value is less than the level of significance, we reject the null hypothesis and conclude that there is sufficient evidence to support the claim that the mean benzene concentration is less in treated water than in untreated water.

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Answer:

see explanation

Step-by-step explanation:

ratio of sides = 8 : 5 : 7 = 8x : 5x : 7x ( x is a multiplier )

given the perimeter = 480 , then

8x + 5x + 7x = 480

20x = 480 ( divide both sides by 20 )

x = 24

then

8x = 8 × 24 = 192

5x = 5 × 24 = 120

7x = 7 × 24 = 168

the sides of the triangle are 192 inches, 120 inches, 168 inches

-------------------------------------------------------------------------------------------

ratio of angles = 8 : 15 : 17 = 8x : 15x : 17x ( x is a multiplier )

the sum of the angles in a triangle = 180° , then

8x + 15x + 17x = 180

40x = 180 ( divide both sides by 40 )

x = 4.5

Then

8x = 8 × 4.5 = 36

15x = 15 × 4.5 = 67.5

17x = 17 × 4.5 = 76.5

the angles in the triangle are 36°, 67.5°, 76.5°

The appropriate test to compare the satisfaction scores before and after the introduction of the new service is a paired t-test or a dependent t-test.

This is because the same group of customers is being surveyed before and after the introduction of the new service. The two samples are not independent of each other, but are related or dependent because they are measuring the same thing in the same individuals at different points in time.

A paired t-test compares the means of two related samples and determines whether the difference between them is statistically significant or simply due to chance. In this case, the null hypothesis would be that there is no significant difference in customer satisfaction before and after the introduction of the new service, and the alternative hypothesis would be that there is a significant difference.

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Since f(x) is an increasing function (i.e., its derivative is always positive), it satisfies the conditions of Theorem 9, the Intermediate Value Theorem.

A continuous function is a mathematical function in which arbitrarily small changes in the input result in arbitrarily small changes in the output.

In other words, a function is b if, for every input value in its domain, the output value exists, the limit exists, and the limit equals the function value. It can also be defined as a function whose graph is a single unbroken curve, meaning that there are no abrupt jumps, gaps, or holes.

Using theorems 4, 5, 7, and 9, explain why the function is continuous at every number in its domain and state the domain: f(x) = (3x + 7) / (2x - 5); Domain: R \ {5/2}; Continuous on its domain as it is a quotient of two continuous functions and there are no vertical asymptotes, holes or jumps in the graph.

The domain of f(x) is all real numbers since there are no restrictions on the values of x for which the function is defined.

To prove that f(x) is continuous at every number in its domain, we need to show that it satisfies the conditions of Theorem 4, which states that a function is continuous at a point if and only if the limit of the function exists at that point and is equal to the value of the function at that point.

In this case, we have:

The limit of f(x) as x approaches any number a is given by:

lim(x→a) f(x) = lim(x→a) (2x + 3) = 2a + 3

The value of f(a) at any number a is given by:

f(a) = 2a + 3

Since the limit of f(x) as x approaches a is equal to f(a), we can conclude that f(x) is continuous at every number in its domain, which is all real numbers.

Furthermore, since f(x) is a polynomial, it is continuous everywhere, which means that it satisfies the conditions of Theorems 5 and 7 as well. Finally, since f(x) is an increasing function (i.e., its derivative is always positive), it satisfies the conditions of Theorem 9, the Intermediate Value Theorem.

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Complete Question:

Using Theorems 4, 5, 7, and 9, explain why the function f(x) = 2x + 3 is continuous at every number in its domain. State the domain.

Answer:

150

Step-by-step explanation:

Given, x+y=15 and x-y=10

We need to find the value of x^2-y^2

We know that x^2-y^2 = (x+y)(x-y)

Substituting the given values, we get:

x^2-y^2 = (x+y)(x-y) = (15)(10) = 150

Therefore, the value of x^2-y^2 is 150.

The z-score for the value 63.49 is approximately 0.24.

What is statistics?

Statistics is a branch of mathematics that deals with the collection, analysis, interpretation, presentation, and organization of numerical data.

Yes, it is possible to calculate a z-score for the value 63.49 assuming that the data follows a normal distribution.

The z-score measures the number of standard deviations a data point is away from the mean of the distribution. To calculate the z-score, we first need to calculate the mean and standard deviation of the dataset.

The mean can be calculated by adding up all the values and dividing by the total number of values:

Mean = (59 + 60 + 61 + 62 + 62 + 63 + 63 + 63 + 64 + 64 + 65 + 66 + 67 + 68) / 14 = 63

The standard deviation can be calculated using the following formula:

Standard deviation = sqrt((1/N) * sum((xi - x_mean)²))

where N is the number of values, xi is each value in the dataset, and x_mean is the mean of the dataset.

Using this formula, we can calculate the standard deviation of the dataset:

Standard deviation = sqrt((1/14) * ((59 - 63)² + (60 - 63)² + ... + (68 - 63)²))

Standard deviation ≈ 2.02

Now we can calculate the z-score for the value 63.49 using the following formula:

z-score = (x - x_mean) / standard deviation

where x is the value we want to calculate the z-score for.

z-score = (63.49 - 63) / 2.02 ≈ 0.24

Therefore, the z-score for the value 63.49 is approximately 0.24.

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For the initial condition y(7) = 6,

(i) For dy/dx = x, the function is y = (x²/2) - (19/2),

(ii) For dy/dx = y, the function is y = 6eˣ⁻⁷.

Part (i) : We can solve the differential equation "dy/dx = x" using separation of variables.

⇒ dy/dx = x,

⇒ dy = x dx,

On integrating,

We have,

⇒ y = x²/2 + C, where C is = constant of integration.

To find the value of C, we can use the initial condition which is y(7) = 6;

⇒ 6 = (7²)/2 + C,

⇒ C = 6 - (49/2),

⇒ C = -19/2,

Therefore, the solution to differential equation "dy/dx = x", for initial condition y(7) = 6, is y = (x²/2) - (19/2),

Part (ii) : We solve differential equation "dy/dx = y" using separation of variables.

⇒ dy/dx = y

⇒ dy/y = dx,

On integrating,

We have,

⇒ ln|y| = x + C, where C is = constant of integration.

Solving for y,

We get,

⇒ y = Ceˣ,

To find the value of C, we can use the initial condition y(7) = 6:

⇒ 6 = Ce⁷,

⇒ C = 6/e⁷,

Therefore, the solution to the differential equation dy/dx = y, for initial condition y(7) = 6, is : y = (6/e⁷) × eˣ,

Simplifying, we get:

⇒ y = 6eˣ⁻⁷,

Therefore, the differential-equation is y = 6eˣ⁻⁷.

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The given question is incomplete, the complete question is

The following differential equations appear similar but have very different solutions. Solve both subject to the initial condition y(7) = 6;

(i) dy/dx = x

y = ____

(ii) dy/dx = y

y = ____

The Moellers had 1,500 miles remaining to reach their destination. On the first day, the Moellers drove 1/2 (or 0.5) of the 3,000 miles, which is 1,500 miles. This means they had 1,500 miles remaining to reach their destination.

On the second day, they drove 1/4 (or 0.25) of the remaining 1,500 miles, which is 375 miles. Therefore, they had 1,125 miles remaining to reach their destination after driving 1/2 on the first day and 1/4 on the second day.

Based on the given information, the Moellers drove 1/3 of the distance on the first day and 1/4 of the remaining distance on the second day. Let's calculate the remaining distance to reach their destination:

Total distance: 3,000 miles

First day: 1/3 of 3,000 miles = 1,000 miles

Remaining distance after the first day: 3,000 - 1,000 = 2,000 miles

Second day: 1/4 of 2,000 miles = 500 miles

Remaining distance after the second day: 2,000 - 500 = 1,500 miles

So, the Moellers had 1,500 miles remaining to reach their destination.

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Answer:

Sure, I can tell you about the four holy sites in Jerusalem. There are actually many holy sites in Jerusalem, but the four most significant ones are the Western Wall, the Church of the Holy Sepulchre, the Dome of the Rock, and the Al-Aqsa Mosque.

The Western Wall, also known as the Wailing Wall, is the most sacred place in Judaism. It is the last remaining part of the Second Temple, which was destroyed by the Romans in 70 CE. Jews from all over the world come to pray at the wall, and many people write prayers on pieces of paper and stuff them in the cracks between the stones.

The Church of the Holy Sepulchre is one of the most important Christian sites in the world. It is believed to be the place where Jesus was crucified, buried, and resurrected. The church is shared by several Christian denominations, including the Greek Orthodox, Roman Catholic, and Armenian Apostolic Churches.

The Dome of the Rock is a Muslim shrine located on the Temple Mount, which is one of the most contested religious sites in the world. The shrine is built on the spot where Muslims believe the Prophet Muhammad ascended to heaven. The Dome is covered in gold and has a beautiful blue mosaic on the inside.

The Al-Aqsa Mosque is the third holiest site in Islam, after Mecca and Medina. It is located on the Temple Mount, next to the Dome of the Rock. The mosque is believed to be the place where the Prophet Muhammad prayed with the other prophets, and it has a beautiful silver dome.

These four holy sites are all located within a few hundred meters of each other, and they are a testament to the deep religious history and significance of Jerusalem. Each site is unique and beautiful in its own way, and they all attract millions of visitors every year.

Step-by-step explanation:

Answer:

2nd one

6th one

Step-by-step explanation:

Hope this helps! Pls give brainliest!

Answer:

2 m/s

Step-by-step explanation:

To find the speed of the ball, we can use the formula:

Speed = Distance / Time

Given that the distance the ball moves is 3 m and the time it takes is 1.5 s, we can substitute those values into the formula to get:

Speed = 3 m / 1.5 s

Simplifying the expression by dividing 3 by 1.5, we get:

Speed = 2 m/s

Therefore, the speed of the ball is 2 m/s.

Only options I and III are (C)'s correct responses.

I. k-fold cross-validation requires fitting the model k times, whereas LOOCV requires fitting the model n times. Since k > n, k-fold cross-validation is more efficient computationally than LOOCV.

II. k-fold cross-validation has an advantage over LOOCV in bias reduction since each training set is a random sample of the data and tends to reduce bias.

III. LOOCV has an advantage over k-fold cross-validation in variance reduction since LOOCV uses almost all the data to fit the model for each test observation, resulting in lower variance in the test error estimate. In contrast, k-fold cross-validation uses only a subset of the data for each training set, which can lead to higher variance in the test error estimate.

In conclusion, assertions I and III are valid, and the proper response is (C) I and III alone.

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The radius of the circle is given as 9

To rewrite the equation of the circle from general form to standard form, we need to complete the square for both x and y terms.

x^2 - 18x + y^2 + 14y + 84 = 0 (Given)

To complete the square for x, we need to add and subtract the square of half the x coefficient (i.e., (18/2)^2 = 81) inside the parentheses:

x^2 - 18x + 81 + y^2 + 14y + 84 - 81 = 0

(x - 9)^2 + (y + 7)^2 - 81 = 0

(x - 9)^2 + (y + 7)^2 = 81

This is the standard form of the equation of a circle, where the center is located at (9, -7) and the radius is √81 = 9.

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The area of the given shape above would be = 169m² while the perimeter of the shape = 52m

To calculate the area of the given shape, the formula that should be used is given below;

Area = a²

where;

a = 13m

area = 13× 13 = 169m²

The perimeter of the shape = 2(a+b)

= 2(13+13)

= 2×26

= 52 m

Therefore, the perimeter and the area of the shape above would be = 52m and 169m² respectively.

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The center of a circle that circumscribes a triangle is known as the circumcenter of the triangle.

The circumcenter is the point of intersection of the perpendicular bisectors of the sides of the triangle. This point is equidistant from the three vertices of the triangle, which means that it lies on the perpendicular bisector of each side.

The circumcenter plays an important role in the geometry of triangles. One of its properties is that it is also the center of the circle that passes through the three vertices of the triangle, which is why it is called the circumcenter. This circle is known as the circumcircle of the triangle.

The circumcircle is a unique circle that can be drawn around any triangle, and its center is always the circumcenter. This circle has several important properties, such as:

The circumcircle passes through the three vertices of the triangle.

The circumcircle is centered at the circumcenter of the triangle.

The circumcircle has a radius that is equal to the distance from the circumcenter to any vertex of the triangle.

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Step-by-step explanation:

The sum of the measures insiqe the quadriateral = 360

   one is angle o = 111   and two of them aare 90 degrees each

so    360 - 111 - 90 - 90 = x = 69 degrees

The confidence interval is about the proportion of heads for the population of coins of that type, not about individual coins.

Therefore, we cannot conclude that any particular coin is unfair or not based on this interval.

The 95% confidence interval (54%, 66%) means that if we were to repeat this experiment many times, using different samples of coins of the same type, and calculate a 95% confidence interval each time, then 95% of those intervals would contain the true proportion of heads for the population of coins of that type.

a) The correct answer is D. The confidence interval is about the proportion of heads, not individual coins.

We cannot conclude that any particular coin is unfair or not based on this interval. It only provides an estimate of the proportion of heads for the population of coins of that type.

b) The correct answer is C. If we spun the same coin many times, we would expect the proportion of heads to be somewhere within the 95% confidence interval (54%, 66%).

c) The correct answer is A. If we randomly selected a coin of that type and spun it many times, we would expect the proportion of heads to be within the 95% confidence interval (54%, 66%).

d) The correct answer is B. The confidence interval does not tell us anything about the fairness of individual coins.

e) The correct answer is A. We can be 95% confident that the true proportion of heads for the population of coins of that type is somewhere within the interval (54%, 66%).

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Step-by-step explanation:

Dogs are 3  out of ( 3+2 =5) of the animals

   3 out of 5  or  3/5 of the animals are dogs

              3/5 * 30 = 18 dogs

The test formula is t = (x₁ - x₂) / √(s₁²/n₁) + (s₂²/n₂))

The rejection region for the test is t < -1.971 or t > 1.971.

The question involves the concepts of hypothesis testing and the two-sample t-test.

Hypothesis testing is a statistical method used to make decisions about a population parameter based on a sample of data. In this case, we are interested in comparing the population mean wearing times for old braces and new bands.

The two-sample t-test is a statistical test used to determine if there is a significant difference between the means of two independent samples. The test involves calculating a test statistic (t-value) that measures the difference between the sample means, relative to the variation within the samples.

Here we have

Two hundred children were randomly assigned, 100 to each group.

A summary of the data is given below.

Old Braces: n₁ = 100, sample mean = 425, s₁ = 45 days;

New Bands: n₂ = 100, sample mean = 385, s₂ = 60 days;

You are interested in conducting a test to determine if the population mean wearing times differ using α = 0.10.

(i) The research hypothesis can be framed as:

H₀ : The population mean wearing times for old braces and new bands are equal.

Hᵃ: The population mean wearing time for old braces and new bands are not equal.

(ii) The test formula for comparing the population mean wearing times of two independent samples can be expressed as:

t = (x₁ - x₂) / √(s₁²/n₁) + (s₂²/n₂))

Where x₁ and x₂ are the sample means, s₁ and s₂ are the sample standard deviations, and n₁ and n₂ are the sample sizes.

(iii) To find the rejection region for the test, we first need to determine the degrees of freedom (df), which can be calculated as:

df = (s₁²/n₁+ s₂²/n₂)² / [(s₁²/n₁)² / (n₁ -1) + (s₂²/n₂)² / (n₂ -1)]

Using the given values, we get:

df = (45²/100 + 60²/100)² / [(45²/100)² / 99 + (60²/100)² / 99] = 185.98

Since we have two tails in the test and an alpha level of 0.10, we need to split the alpha level between the two tails.

Therefore, we can find the critical t-values using a t-distribution table with 185 degrees of freedom and an alpha level of 0.05 (half of 0.10).

For a two-tailed test at an alpha level of 0.05, the critical t-values are approximately ±1.971.

Thus, The rejection region for the test is t < -1.971 or t > 1.971. If the calculated t-value falls outside this range, we reject the null hypothesis in favor of the alternative hypothesis and conclude that the population mean wearing times for old braces and new bands are not equal.

Therefore,

The test formula is t = (x₁ - x₂) / √(s₁²/n₁) + (s₂²/n₂))

The rejection region for the test is t < -1.971 or t > 1.971.

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