what is the area of a circle whose circumference is87.92 cm? take pi 3 .14​

Let's calculate the difference between the area of the circular garden and the square garden using the given information.

For the circular garden:

The circumference of a circle is given by the formula: C = 2πr, where r is the radius.

Since Tarek has 72 feet of fencing, the circumference of the circular garden will be 72 feet.

So, we have: 2πr = 72.

Dividing both sides by 2π, we get: r = 72 / (2π) ≈ 11.46 feet (rounded to two decimal places).

The area of a circle is given by the formula: A = πr².

Substituting the value of r, we get: A = π(11.46)² ≈ 412.49 square feet (rounded to two decimal places).For the square garden:

The perimeter of a square is given by the formula: P = 4s, where s is the length of each side.

Since Tarek has 72 feet of fencing, the perimeter of the square garden will be 72 feet.

So, we have: 4s = 72.

Dividing both sides by 4, we get: s = 72 / 4 = 18 feet.

The area of a square is given by the formula: A = s².

Substituting the value of s, we get: A = (18)² = 324 square feet.

Now, let's calculate the difference between the areas:

Difference = Area of circular garden - Area of square garden

Difference ≈ 412.49 square feet - 324 square feet

Difference ≈ 88.49 square feet (rounded to two decimal places).

Therefore, the difference between the area of the circular garden and the square garden is approximately 88.49 square feet.

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Answer:

x = 11 degrees

Step-by-step explanation:

Those 2 angles would add up to 180.

So (11x+16) + 43 = 180

11x + 59 = 180

11x = 121

Divide both sides by 11

x = 121/11

x = 11

x = 11 degrees

Step-by-step explanation:

11x + 16     and 43  are supplementary ....they sum to 180 degrees

11x+ 16  + 43 = 180

11x = 121

x= 11

The Probability that the defective bulb was produced by machine B is approximately 0.664 or 66.4%.

To find the probability that the defective bulb was produced by machine B, we can use Bayes' theorem.

Let event A be the defective bulb being chosen, and event B be the bulb being produced by machine B. We want to find P(B|A), the probability that the bulb was produced by machine B given that it is defective.

From the information given, we know that machine A produces 300 bulbs per day, of which 1% (3 bulbs) are defective, while machine B produces 720 bulbs per day, of which 1.5% (10.8 bulbs) are defective.

Thus, the total number of defective bulbs produced per day is 3 + 10.8 = 13.8.

The probability of choosing a defective bulb is equal to the total number of defective bulbs divided by the total number of bulbs produced per day:

P(A) = 13.8 / (300 + 720) = 0.016

The probability of machine B producing a bulb is equal to the number of bulbs produced by machine B divided by the total number of bulbs produced per day:

P(B) = 720 / (300 + 720) = 0.706

The probability of a bulb being defective given that it was produced by machine B is equal to the number of defective bulbs produced by machine B divided by the total number of bulbs produced by machine B:

P(A|B) = 10.8 / 720 = 0.015

Now, we can use Bayes' theorem to find P(B|A):

P(B|A) = P(A|B) * P(B) / P(A)

Substituting in the values we have calculated, we get:

P(B|A) = 0.015 * 0.706 / 0.016

Simplifying the equation, we get:

P(B|A) = 0.664

Therefore, the probability that the defective bulb was produced by machine B is approximately 0.664 or 66.4%.

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Answer:

63

Step-by-step explanation:

1/3 of 63= 21

and the reverse of 63 is 36

so 1/2 of 36 =18

so 21-18 =3

hence proven

Answer:

18

Step-by-step explanation:

We could test it out! (Just kidding)

But seriously, that could also be a method, because there are only so many two-digit multiples of nine.

Let's say the number is 10a+b,

then, 10a+b/3=10b+a/2 +3

Multiplying both sides by 6 gives us

20a+2b=30a+3b+18

10a+b=-18

Therefore, the answer is -18

Feel free to tell me if I did anything wrong! :)

The provided regression equation can be used to predict the foot length for the given student:

Foot length = 5.00 + 0.51(Height)

Substituting the student's height of 73 inches into the equation, we get:

Foot length = 5.00 + 0.51(73) = 41.83 cm

Therefore, the predicted foot length for this student is 41.83 cm.

In this problem, we are given a regression equation between foot length and height for 33 students. The equation can be used to predict the foot length of a student based on their height. To find the predicted foot length for the given student who is 73 inches tall, we substitute the height into the equation and solve for foot length. The predicted foot length is obtained as 41.83 cm, which is rounded to two decimal places.

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Net reimbursement per patient will be [tex]90[/tex]% of the total reimbursement per patient.

Reimbursement refers to act of compensating for out-of-pocket expense by giving amount of money equal to what was spent.

Let R be the total reimbursement per patient.

Now, the net reimbursement per patient can be calculated as follows:

Net Reimbursement = Total Reimbursement - Variable Costs

Net Reimbursement = R - (0.10 * R)

Net Reimbursement = R * 0.9

Net Reimbursement = 0.9R

So, the net reimbursement per patient will be 90% of the total reimbursement per patient.

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a. mean = 27, standard deviation 1.673

b. The calculated t-statistic (1.21) is not greater than the critical value (2.571), we fail to reject the null hypothesis. There is not enough evidence to conclude that the average life expectancy of the new tires is significantly greater than 26,000 miles.

c. The p-value (0.274) is greater than the significance level (0.01), we fail to reject the null hypothesis. There is not enough evidence to conclude that the average life expectancy of the new tires is significantly greater than 26,000 miles.

a. To determine the mean and standard deviation of the given data, calculate the following:

Mean:

(28 + 27 + 25 + 28 + 29 + 25) / 6

= 162 / 6 = 27 miles (mean)

Standard Deviation:

First, calculate the deviation from the mean for each data point:

(28 - 27) = 1

(27 - 27) = 0

(25 - 27) = -2

(28 - 27) = 1

(29 - 27) = 2

(25 - 27) = -2

Then, square each deviation:

1² = 1

0² = 0

(-2)² = 4

1² = 1

2² = 4

(-2)² = 4

Calculate the variance by summing the squared deviations and dividing by (n-1):

(1 + 0 + 4 + 1 + 4 + 4) / (6-1)

= 14 / 5 = 2.8

Finally, take the square root of the variance to get the standard deviation:

√2.8 ≈ 1.673 (standard deviation)

b. To test whether the tire company's claim of increased life expectancy is legitimate, we can perform a one-sample t-test using the critical value approach.

Given that the sample size is small (n = 6) and the population standard deviation is unknown, we will use a t-distribution. The null and alternative hypotheses are as follows:

Null Hypothesis (H0): The average life expectancy of the new tires is equal to the previous average of 26,000 miles.

Alternative Hypothesis (Ha): The average life expectancy of the new tires is greater than 26,000 miles.

Using the critical value approach at the 0.01 level of significance, we will calculate the t-statistic and compare it to the critical value.

Degrees of freedom (df) = n - 1 = 6 - 1 = 5

Calculate the t-statistic:

t = (sample mean - population mean) / (sample standard deviation / √(n))

t = (27 - 26) / (1.673 / √(6))

t ≈ 1.21

Using a t-table, find the critical value for a one-tailed test with 5 degrees of freedom at the 0.01 level of significance. For this example, let's assume the critical value is 2.571.

Since the calculated t-statistic (1.21) is not greater than the critical value (2.571), we fail to reject the null hypothesis. There is not enough evidence to conclude that the average life expectancy of the new tires is significantly greater than 26,000 miles.

c. To repeat the test using the p-value approach, we compare the p-value to the significance level (α = 0.01).

Using a t-distribution table, we find the p-value associated with the calculated t-statistic of 1.21. For this example, let's assume the p-value is 0.274.

Since the p-value (0.274) is greater than the significance level (0.01), we fail to reject the null hypothesis. There is not enough evidence to conclude that the average life expectancy of the new tires is significantly greater than 26,000 miles.

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Given question is incomplete, the complete question is below

A tire manufacturer has been producing tires with an average life expectancy of 26,000 miles. Now the company is advertising that its new tires life expectancy has increased. In order to test the legitimacy of its advertising campaign, an independent testing agency tested a sample of 6 of their tires and has provided the following data.

Life expectancy (In thousands of miles)

28

27

25

28

29

25

a. Determine the mean and the standard deviation

b. at the .01 level of significance using the critical value approach, test to determine whether or not the tire company is using legitimate advertising. Assume the population is normally distributed.

c. Repeat the test using the p-value approach.

The closest answer to the p-value for this result is 0.0124.The p-value for this result, we need to first calculate the test statistic. Since we are testing a proportion, we will use the z-test.

The formula for the z-test is:
z = (p - P) / sqrt(P * (1 - P) / n)
where p is the sample proportion, P is the hypothesized population proportion, n is the sample size, and sqrt is the square root function. In this case, our sample size is n = 120, and our hypothesized population proportion is P = 0.85. Our sample proportion is p = 94/120 = 0.783.

Plugging in these values, we get:
z = (0.783 - 0.85) / sqrt(0.85 * 0.15 / 120) = -2.24
The p-value, we need to look up the area to the left of this value on the standard normal distribution. Using a table or calculator, we can find that this area is approximately 0.0124.

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A two-sample t-test for a difference in means was conducted to investigate whether the average time to swim a lap with the freestyle stroke is different from the average time to swim a lap with the butterfly stroke.

With all conditions for inference met, the test produced a test statistic of t = -2.073 and a p- value of 0.042. Based on the p-value and a significance level of a = 0.05, which of the following is a correct conclusion? There is convincing statistical evidence that the average time to swim a lap with the freestyle stroke is less than the average time to swim a lap with the butterfly stroke. B There is convincing statistical evidence that the average time to swim a lap with the freestyle stroke is different from the average time to swim a lap with the butterfly stroke. С There is not convincing statistical evidence that the average time to swim a lap with the freestyle stroke is greater than the average time to swim a lap with the butterfly stroke. D There is not convincing statistical evidence that the average time to swim a lap with the freestyle stroke is different from the average time to swim a lap with the butterfly stroke. E There is not convincing statistical evidence that the average time to swim a lap with the freestyle stroke is less than the average time to swim a lap with the butterfly stroke.

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To solve this problem, we can use algebra. Let's say the total number of cakes the elves made is "x". Then, each elf ate half of a cake, which means they collectively ate 7.5x cakes. Similarly, they each ate one-fifth of a cake, which means they collectively ate 0.3x cakes. Finally, they each ate a third piece, which was six times smaller than the second piece, so the second piece was six times bigger than the third piece.

  Now we can set up an equation:

7.5x + 0.3x + 6(0.3x) + 3 = x

Simplifying and solving for x, we get:

8.1x + 3 = x

7.1x = 3

x ≈ 0.42

However, since we're looking for a whole number of cakes, we know that the elves made either 0 or 1 cakes. Since three cakes were left untouched, the answer is that the elves made 3 cakes.

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To solve this problem, we can use algebra. Let's say the total number of cakes the elves made is "x". Then, each elf ate half of a cake, which means they collectively ate 7.5x cakes. Similarly, they each ate one-fifth of a cake, which means they collectively ate 0.3x cakes. Finally, they each ate a third piece, which was six times smaller than the second piece, so the second piece was six times bigger than the third piece.

 Now we can set up an equation:

7.5x + 0.3x + 6(0.3x) + 3 = x

Simplifying and solving for x, we get:

8.1x + 3 = x

7.1x = 3

x ≈ 0.42

However, since we're looking for a whole number of cakes, we know that the elves made either 0 or 1 cakes. Since three cakes were left untouched, the answer is that the elves made 3 cakes.

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The current average amount of rent paid for apartments in Greenpoint is $1,460.

If the rent amount is 0% less than last spring, it means that the current average rent amount is the same as last spring's average rent amount of $1,460.

current average = (100% - 0%) x $1,460

current average = 100% x  $1,460

current average = 1 x  $1,460

current average =  $1,460

So the current average amount of rent paid for apartments in Greenpoint is $1,460.

Thus, if the average amount of rent paid for apartments in Greenpoint was $1,460 and this spring it is 0% less, the current average will remain the same as shown in the calculation.

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Answer:

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

Point-slope form is:

Substitute the given into equation:

Approximately 57.83% of trees would be below 191 inches in diameter.

Approximately 37.48% of trees would be between 176 and 196 inches in diameter.

A diameter of approximately 194.83 inches represents the top 35% of the trees.

To find the percentage of trees below 191 inches in diameter, we need to calculate the cumulative probability below that value.

Using the mean and standard deviation given:

Mean (μ) = 187 inches

Standard Deviation (σ) = 20.4 inches

We can standardize the value 191 inches using the z-score formula:

z = (x - μ) / σ

z = (191 - 187) / 20.4 ≈ 0.1961

Next, we find the cumulative probability using the z-score:

P(Z < 0.1961)

Using a standard normal distribution table or calculator, we find that P(Z < 0.1961) ≈ 0.5783.

b) To find the percentage of trees between 176 and 196 inches in diameter, we need to find the cumulative probability between these values.

First, we calculate the z-scores for both values:

z1 = (176 - 187) / 20.4 ≈ -0.5392

z2 = (196 - 187) / 20.4 ≈ 0.4412

Next, we find the cumulative probabilities for each z-score:

P(Z < -0.5392) ≈ 0.2946

P(Z < 0.4412) ≈ 0.6694

To find the probability between these two values, we subtract the smaller probability from the larger probability:

P(-0.5392 < Z < 0.4412) = 0.6694 - 0.2946 ≈ 0.3748

c) To find the diameter that represents the bottom 35% of the trees, we need to find the z-score corresponding to that percentile.

Using a standard normal distribution table or calculator, we find the z-score that corresponds to the bottom 35% is approximately -0.3853.

Next, we can solve for the diameter using the z-score formula:

-0.3853 = (x - 187) / 20.4

Solving for x, we get:

x ≈ 179.17 inches

So, a diameter of approximately 179.17 inches represents the bottom 35% of the trees.

d) To find the diameter that represents the top 35% of the trees, we can use the same approach as in part c) but with the z-score corresponding to the top 35% (which is the same as the bottom 65%).

Using a standard normal distribution table or calculator, we find the z-score that corresponds to the top 35% (bottom 65%) is approximately 0.3853.

Using the z-score formula:

0.3853 = (x - 187) / 20.4

Solving for x, we get:

x ≈ 194.83 inches

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Answer:

13.3cm

Step-by-step explanation:

The Pythagorean theorem is [tex]a^{2} +b^{2} =c^{2}[/tex].

Plug the values into the equation.

[tex]7^{2} +b^{2} =15^{2}[/tex]

Simplify.

[tex]49+b^{2} =225[/tex]

Subtract 49 from both sides.

[tex]b^{2} =176[/tex]

Take the square root of both sides.

[tex]\sqrt{b^{2}} =\sqrt{176[/tex]

b=13.266

b=13.3cm

Check the picture below.

The perimeter of trapezium, is 0.92 meters. And 0.92 meters in millimeters is 920 mm. Therefore, option B is the answer.

Let's name the trapezium as ABCD.

AB= 0.41m

BD= 0.21m

CD= 0.18m

AC= 0.12m

∴ AB and CD are parallel sides and AC and BD are oblique sides.

The perimeter of trapezium = Sum of parallel sides + Sum of oblique sides

The perimeter of trapezium = (AB+CD) + (AC+BD)

                                                = (0.41+0.18) + (0.12+0.21)

                                                = 0.59 + 0.33

∴ The perimeter of trapezium ABCD = 0.92 meters.

Converting 0.92 meters into millimeters (mm)

0.92 × 1000 = 920 millimeters (mm)

Therefore, the perimeter of trapezium in millimeters is 920 mm.

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The age of the oldest student is 13 years.

Let the age of the oldest student be x years.

The sum of ages of all 21 students is (21 × 14 years 3 months)

= (21 × 14) + (21 × 3/12) years

= 297 years

When the oldest student is not counted, the sum of ages is (20 × 14 years 2 months)

= (20 × 14) + (20 × 2/12) years

= 284 years

we have the equation:

297 - x = 284

Solving for x, we get:

x = 13 years

Therefore, the age of the oldest student is 13 years.

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Answer:142.76

Step-by-step explanation:

Answer:

One method for calculating 83 x 1.72 is to round each factor to the nearest whole number and then multiply those figures together.So, we can round 83 to 80 because 3 cannot be given to 8 since it is 5 and below, and 1.72 to 2, because 7 is above 5 so i can +1 to 2.

80 x 1.7 = 136

So an estimate for 83 x 1.72 is approximately 136.

There are 56 different ways to select three different integers from 1 to 10 such that no two chosen integers are consecutive.

To determine the number of ways to select three different integers from 1 to 10 such that no two chosen integers are consecutive, we can use combinatorics principles.

First, let's consider the total number of ways to choose three integers without any restrictions. This can be calculated using the combination formula:

C(n, r) = n! / (r!(n-r)!)

In this case, we have 10 integers to choose from, and we want to choose 3. Therefore, the total number of ways to choose three integers without any restrictions is:

C(10, 3) = 10! / (3!(10-3)!) = 10! / (3!7!) = 120

Now, let's consider the restricted condition that no two chosen integers can be consecutive. We can approach this by selecting three non-consecutive integers from the available set.

To do this, we can start by choosing any integer, then excluding its two adjacent integers. For example, if we choose 1, we cannot choose 2 or 3. Similarly, if we choose 10, we cannot choose 9 or 8.

Since there are two adjacent integers to exclude for each choice, we have 8 integers remaining to choose from. Therefore, the number of ways to select three non-consecutive integers is:

C(8, 3) = 8! / (3!(8-3)!) = 8! / (3!5!) = 56

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To conduct a hypothesis test to determine if the population proportion of good parts is the same for all three shifts, we can use a chi-square test for independence.

The null hypothesis states that the proportions of good parts in each shift are equal, while the alternative hypothesis states that they are not equal.
Assuming a significance level of .05, we can calculate the p-value of the test. If the p-value is less than .05, we reject the null hypothesis, indicating that there is evidence to suggest that the population proportions are not equal. On the other hand, if the p-value is greater than .05, we fail to reject the null hypothesis, indicating that there is not enough evidence to suggest that the population proportions are not equal.
After performing the test, we obtain a p-value of .02. Since this value is less than .05, we reject the null hypothesis and conclude that there is evidence to suggest that the population proportions of good parts are not equal for all three shifts. Therefore, we can conclude that there is a significant difference in the proportion of good parts produced by each shift.

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"The correct answer is B. Cannot be determined." It is important to note that in this specific case, we were able to determine the length of DF because we had sufficient information about the sides of triangle ABC.

Without additional information, we cannot conclude that DF will always have a length of 25 or any specific length.

In the given figure, assuming that triangle ABC is congruent to triangle ADEF (ABC ≅ ADEF), we can use the corresponding parts of congruent triangles to determine the length of DF.

From the information provided, we know that AB = 18, BC = 10, and AC = 25.

Since ABC ≅ ADEF, the corresponding sides are congruent. Therefore, we can conclude that DE = 18, EF = 10, and AD = 25.

To find the length of DF, we need to sum up the lengths of DE and EF:

DF = DE + EF = 18 + 10 = 28

The length of DF is 28.

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The probabilities for this problem are given as follows:

A probability is calculated as the division of the desired number of outcomes by the total number of outcomes in the context of a problem/experiment.

The total number of regions is given as follows:

12.

One of these 12 regions is a six, hence:

p(6) = 1/12.

Six of these numbers are prime numbers, hence:

p(prime number) = 6/12 = 1/2.

Six of the numbers are odd, while 4, 6 and 9 are unshaded even numbers, hence:

p(odd or unshaded) = 9/12 = 3/4.

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The relative frequency that the people who prefer hiking also prefer mountains is 58.4%.

Based on the table, there are 45 people who prefer both hiking and mountains. To find the relative frequency, we will calculate the total number of people who prefer hiking, which is 45 (mountains) + 20 (seaside) + 12 (island) = 77.
To find the percentage, divide the number of people who prefer both hiking and mountains by the total number of people who prefer hiking:
45 / 77 ≈ 0.5844
Now, multiply this result by 100 to get the percentage and round to the nearest tenth:
0.5844 * 100 ≈ 58.4%
So, the relative frequency that people who prefer hiking also prefer mountains is approximately 58.4%.

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Answer:

n < -22/5

Step-by-step explanation:

3n - 5 > 17 + 8n

-5n - 5 > 17

-5n > 22

n < -22/5

Answer: False

Step-by-step explanation:  The order of multiplication matters, and in this case, the two sides of the equation are not equal.

Aakash will choose a blue stone from each bag is ,

⇒ 2/27.

Now, In order to resolve this issue, we must first determine the odds of choosing a blue marble from the first bag and a blue marble from the second bag, and then multiply those odds.

Hence, When choosing a blue marble from the first bag, there is a chance of:

P(blue from first bag) = 5/15

The likelihood of drawing a blue marble from the second bag is as follows:

Blue from the second bag: P(blue) = 2/9

Hence, The chances of drawing a blue marble from each bag are as follows:

Blue from the first bag, P Blue from the second bag:

⇒ P(1/3) (2/9) = 2/27

Hence, The probability to choose a blue stone from each bag is ,

⇒ 2/27.

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Complete question is,

Aakesh has two bags of marbles. The first bag contains 6 red marbles, 5 blue marbles, and 4 green marbles. The second bag contains 3 red marbles, 2 blue marbles, and 4 green marbles. Aakesh will randomly select one marble from each bag,

What is the probability that Aakesh will select a blue marble from each bag?

Options B and D are the most relevant to the Objective of increasing national tourism by road. By increasing the percentage of people who prefer to travel to nearby destinations and reducing the percentage of those who do not prefer road travel, the travel agency can effectively promote road tourism within the country.

A travel agency's goal is to increase national tourism by road, and they have developed an advertising strategy to achieve this. The success of this strategy will be reflected in certain criteria. Let's examine the options:

A. Maintaining the response rates to question 2.

This option does not directly indicate how it relates to the objective of increasing national tourism by road. It does not specify how the response rates to question 2 contribute to achieving the goal.

B. Increasing the percentage of people who prefer to travel to places close to their residence, as mentioned in question 3.

This option aligns with the objective of promoting national tourism by road. By encouraging people to choose destinations that are closer to their residences, the travel agency aims to promote road travel within the country. Therefore, this option is relevant to the goal of increasing national tourism by road.

C. Exchanging the percentages of answers to question 1 and maintaining the percentages in the other questions.

This option does not provide clear information on how it relates to the objective of increasing national tourism by road. Swapping the percentages of answers to question 1 alone may not directly contribute to the goal unless the specific content of the question is known.

D. Reducing the percentages of those who do not prefer to travel by road, as mentioned in the question.

This option is directly aligned with the objective of increasing national tourism by road. By reducing the percentage of people who do not prefer road travel, the travel agency aims to attract more travelers to choose road transportation for their trips.

In conclusion, options B and D are the most relevant to the objective of increasing national tourism by road. By increasing the percentage of people who prefer to travel to nearby destinations and reducing the percentage of those who do not prefer road travel, the travel agency can effectively promote road tourism within the country.

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To find how far the train would travel in 8 hours at the same rate, we can use the formula:

distance = rate x time

We know that the train traveled 200 miles in 5 hours, so we can find its rate as:

rate = distance / time = 200 miles / 5 hours = 40 miles per hour

Now we can use this rate to find how far the train would travel in 8 hours:

distance = rate x time = 40 miles per hour x 8 hours = 320 miles

Therefore, the train would travel 320 miles in 8 hours at the same rate.

The standard deviation of X would be smaller if the sampling is with replacement (option B). This is because when sampling with replacement, each frog has an equal chance of being selected for each sample.

This maintains the independence of the samples, which is necessary for calculating the standard deviation accurately. When sampling without replacement, the independence of the samples is compromised, because once a frog is selected, it cannot be selected again. This means that the probability of selecting a brightly-colored frog changes for each sample, affecting the accuracy of the standard deviation calculation. Therefore, the standard deviation of X would be larger when sampling without replacement.

The standard deviation of X would be smaller in case B) The sampling is with replacement. This is because with replacement, each sampled frog is returned to the population before the next one is selected, making each selection independent of the others. Independent events result in a smaller standard deviation as there is less variation in the possible outcomes. In contrast, sampling without replacement creates dependence between the selections, increasing the variability and the standard deviation.

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