is 3+5(9+2n)equal to48+5n

The number of penguins in the water as; 7 penguins. The total number of penguins as; 21 penguins

Since solving real-life cases with the use of arithmetic operations.

Let we are given: There are 14 penguins on the ice.

Half, as many are swimming, implies that: 7 of them are swimming

Thus, the number of penguins in water = 7 penguins

The total number of penguins overall = penguins in water + penguins on the ice

The total number of penguins overall = 7 + 14

The total number of penguins overall = 21 penguins

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The total number of different types of jeans available is 30. The correct answer is e. 30.

Since each design can be made with either short or long length, and there are 3 designs in total, there are 2 options for length for each design.

Additionally, there are 5 color patterns available for each design and length combination.

Therefore, the total number of different types of jeans available can be calculated as follows:

2 (options for length) x 3 (designs) x 5 (color patterns) = 30.

Therefore, there are 30 different types of jeans offered in all.

Hence, the correct answer is an option (e).

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Let's assume the price of commodity B is "x". Then, according to the given information, the price of commodity A would be 20% more than "x", which is equal to 1.2x. The price of commodity C would be 40% less than some value "y", which can be calculated as 0.6y.

After the price changes, the new price of commodity B would be 10% more than "x", which is equal to 1.1x. The new price of commodity C would be 10% less than "y", which is equal to 0.9y.

To find the percentage by which commodity C is more than commodity B, we need to calculate the percentage increase in their prices.

The new price of commodity B is 1.1x, which is 10% more than x. Therefore, the percentage increase in the price of commodity B is:

(1.1x - x)/x x 100% = 10%

The new price of commodity C is 0.9y, which is 10% less than y. Therefore, the percentage decrease in the price of commodity C is:

(y - 0.9y)/y x 100% = 10%

We can simplify this expression to:

0.1/0.9 x 100% = 11.11%

Therefore, commodity C is approximately 11.11% more expensive than commodity B after the price changes.

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Simplifying the logarithmic expressions:

a. log(12) + 10 log(5)

Using the product rule of logarithms: log(a) + log(b) = log(a * b)

[tex]= log(12 * (5)^10)[/tex]

= log(12 * 9765625)The simplified expression is log(117187500).

b. log(400) - log(80)

Using the quotient rule of logarithms: log(a) - log(b) = log(a / b)

= log(400 / 80)

= log(5)

The simplified expression is log(5).c. 5 log(0.2) + log(3) - log(6)

Using the power rule of logarithms: [tex]log(a^n) = n * log(a)[/tex]

= [tex]log(0.2^5) + log(3) - log(6)= log(0.00032) + log(3) - log(6)[/tex]

The simplified expression is log(0.00032) + log(3) - log(6).

Evaluating the logarithmic expressions:

a. log(625)

Using the change of base formula: log(a, b) = log(c, b) / log(c, a)

= log(10, 625) / log(10, 10)

= log(625) / 1

The simplified expression is log(625).

b. 10 log(4) + log(12)

Using the change of base formula: log(a, b) = log(c, b) / log(c, a)= 10 log(4) + log(12) / log(10)

= 10 log(4) + log(12)

The simplified expression is 10 log(4) + log(12).

c. 10 log(9)Using the change of base formula: log(a, b) = log(c, b) / log(c, a)

= log(10, 9) / log(10, 10)

= log(9) / 1

The simplified expression is log(9).

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An 80% confidence interval for the population mean H is (42.56, 47.68).

Part 1:

The formula for a confidence interval for the population mean is:

CI = x ± z*(σ/√n)

where x is the sample mean, σ is the population standard deviation, n is the sample size, and z is the critical value from the standard normal distribution corresponding to the desired confidence level.

For an 80% confidence interval, the z-value is 1.28 (obtained from a standard normal distribution table). Plugging in the values, we get:

CI = 45.12 ± 1.28*(8.9/√50) = (42.56, 47.68)

Therefore, an 80% confidence interval for the population mean H is (42.56, 47.68).

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The consequence of violating the assumption of Sphericity can be significant. It reduces statistical power, effects the distribution of the F-statistic, and raises the rate of Type I errors in post hocs.

Sphericity refers to the homogeneity of variances between all possible pairs of groups in a repeated-measures design. When this assumption is violated, it can result in a distorted F-statistic, which in turn affects the results of post hoc tests.
The correct answer to the question is c. It reduces statistical power, effects the distribution of the F-statistic, and raises the rate of Type I errors in post hocs. This means that violating the assumption of Sphericity leads to a decreased ability to detect true effects, an inaccurate representation of the true distribution of the F-statistic, and an increased likelihood of falsely identifying significant results.
According to statistics, the consequence of violating the assumption of Sphericity is not a rare occurrence. Therefore, it is essential to ensure that the assumptions of your statistical analysis are met before interpreting your results to avoid false conclusions.
In conclusion, violating the assumption of Sphericity can have severe consequences that affect the validity of your research results. Therefore, it is crucial to understand this assumption and check for its violation to ensure the accuracy and reliability of your statistical analysis.

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Are you good with basic maths

Answer:

f(x)=3*3+8*2-7x-4 = 9x + 5

g(2)=2x-6 = 2(x-3)

The answer is 7.99996224.

To find the area of the region described, we first need to determine the points of intersection between the three equations. The first two equations intersect when 8,192 √x = 128x^2. Simplifying this equation, we get x = 1/64. Plugging this value back into the equation y = 8,192 √x, we get y = 8.
The second and third equations intersect when 128x^2 = y = 8,192 √x. Simplifying this equation, we get x = 1/512. Plugging this value back into the equation y = 128x^2, we get y = 1.
Therefore, the region described is bounded by the lines y = 8, y = 8,192 √x, and y = 128x^2. To find the area of this region, we need to integrate the difference between the two functions that bound the region, which is (8,192 √x) - (128x^2), with respect to x from 1/512 to 1/64.
Evaluating this integral gives us the exact area of the region, which is 7.99996224 square units. Therefore, the answer is 7.99996224.

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In the given frequency table, the relative frequency of 24 represents the proportion of family members who chose to go on a hike out of the total number of family members.

To calculate the relative frequency, we divide the frequency of the specific category (in this case, hike) by the total frequency. In this case, the frequency of the hike is 24, and the total frequency is 38.

Relative Frequency = Frequency of Hike / Total Frequency

Relative Frequency = 24 / 38

Simplifying the fraction, we get:

Relative Frequency ≈ 0.632

So, the relative frequency of 24 represents approximately 0.632 or 63.2%. This means that around 63.2% of the family members chose to go on a hike at the family reunion.

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If there is a positive correlation between x and y in the regression equation y = bx + a, then b > 0.

In the regression equation, y = bx + a, a positive correlation between x and y indicates that as the value of x increases, the value of y also increases, and vice versa. The correlation between these two variables is represented by the coefficient b in the equation.

A positive correlation means that b > 0, as a positive value for b will result in y increasing when x increases. On the other hand, if b < 0, it would indicate a negative correlation, meaning that y would decrease as x increases.

The constant term a in the equation represents the y-intercept or the value of y when x is equal to zero. It does not directly affect the correlation between x and y, so it can be either positive (a > 0) or negative (a < 0) depending on the specific data being analyzed. The value of a will only shift the position of the regression line on the graph, while the slope (b) determines the direction of the correlation between the variables.

In conclusion, if there is a positive correlation between x and y in the regression equation y = bx + a, then b > 0. The values of a > 0 or a < 0 are not directly related to the correlation between x and y.

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In which the altitude from D to side AB bisects AB, the angles of the rhombus are: 120, 60, 120, and 60.

An angle is formed when two straight lines or rays meet at a common endpoint. The common point of contact is called the vertex of an angle. The word angle comes from a Latin word named ‘angulus,’ meaning “corner.”

To solve this question, we need to know the basic theory related to the quadrilateral. As we know rhombus is a type of quadrilateral and also It is a special case of a parallelogram, whose diagonals intersect each other at 90 degrees. Here, by using various theorems or properties we will Find the angles of the rhombus.

Given that ABCD is a Rhombus and DE is the altitude on AB then AE = EB

In a △AED and △BED,

DE = DE (common line)

∠AED = ∠BED (right angle)

AE = EB (DE is an altitude)

∴ △AED ≅ △BED (SAS property)

∴ AD = BD (by C.P.C.T)

But AD = AB ( Sides of rhombus are equal)

[tex]\rightarrow \sf AD = AB = BD[/tex]

∴ ABD is an equilateral triangle.

[tex]\sf \therefore\angle A = 60^0[/tex]

[tex]\sf \rightarrow\angle A =\angle C = 60^\circ[/tex] (opposite angles of a rhombus are equal)

Always, when we add adjacent angles of a rhombus, it is supplementary in nature.

[tex]\sf \angle ABC + \angle BCD = 180^0[/tex]

[tex]\sf \rightarrow \angle ABC + 60^0=180^0[/tex]

[tex]\sf \rightarrow \angle ABC = 180^0-60^0=120^0[/tex]

[tex]\sf \therefore \angle ABC = \angle ADC = 1200[/tex]. (opposite angles of rhombus are equal)

∴ Angles of rhombus are ∠A = 60° and ∠C = 60°, ∠B = ∠D = 120°.

Therefore, option (B) is the correct answer.

Note: Rhombus has all its sides equal and so does a square. Also, the diagonals of any square are perpendicular (means 90°) to each other and bisect the opposite angles. Therefore, a square is a type of rhombus. In rhombus the opposite angles are equal to each other. Also, in rhombus the diagonals bisect these angles.

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ABCD is a rhombus in which Altitude from D to side AB bisects AB. Find the angles of the rhombus? Altitude from D to side AB bisects AB.

A. 110, 70, 110, 70

B. 120, 60, 120, 60

C. 125, 55, 125, 55

D. 135, 45, 135, 45

To find the value of angle h in the given decagon, we can use the fact that the sum of all the interior angles of a decagon is equal to (n - 2) * 180 degrees, where n is the number of sides of the polygon.

In this case, a decagon has 10 sides, so the sum of its interior angles is (10 - 2) * 180 = 8 * 180 = 1440 degrees.

To find angle h, we subtract the sum of the known angles from the total sum of the interior angles:

h = 1440 - (150 + 140 + 150 + 160 + 165 + 170 + 115 + 130 + 140)

h = 1440 - 1370

h = 70

Therefore, the value of angle h in the given decagon is 70 degrees.

The statement you made is not entirely correct. The Second Shape Theorem, also known as the Second Derivative Test, does not include the converse of the First Shape Theorem. Instead, it provides additional information about the nature of critical points of a function.

The Second Shape Theorem states that if a function f(x) has a critical point at x = a (i.e., f'(a) = 0), and if f''(a) exists and is nonzero, then the function has a local minimum at x = a if f''(a) > 0, and a local maximum at x = a if f''(a) < 0.

Note that this theorem only applies to critical points where f'(a) = 0. There may be other critical points where f'(a) does not equal zero, and these points do not satisfy the conditions of the Second Shape Theorem.

In contrast, the converse of the First Shape Theorem states that if a function is differentiable at a point x = a and f'(a) = 0, then f has an extreme value at x = a. This is a separate theorem that is not directly related to the Second Shape Theorem.

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The Second Shape Theorem states that if a function f(x) has an extreme value at x=a, then the function must also be differentiable at x=a. This theorem is the converse of the First Shape Theorem, which states that if a function is differentiable at a point, then it must have a local extreme value at that point.

Essentially, the Second Shape Theorem tells us that having an extreme value at a point is a necessary condition for differentiability at that point. This theorem is particularly useful in calculus and optimization problems, where we are interested in finding the maximum or minimum values of a function. By checking for extreme values and differentiability at those points, we can determine if a function has a local maximum or minimum.

Your statement, "If f(x) has an extreme value at x=a, then f is differentiable at x=a," is actually the converse of the First Shape Theorem. However, this statement is not universally true, as extreme values can occur at non-differentiable points (e.g., sharp corners or endpoints). The Second Shape Theorem does not include the converse of the First Shape Theorem, but rather provides another method for identifying extreme values by analyzing the second derivative.

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The solution of the compound inequality is 4 ≤ x ≤ 6.

The solution of the compound inequality is calculated as follows;

The given inequality equation;

2 + x ≤ 3x – 6 ≤ 12

Break down the compound inequality into two equations as;

2 + x ≤ 3x – 6

add 6 to both sides of the equation;

2 + 6 + x ≤ 3x

8 + x ≤ 3x

Subtract x from both sides of the equation;

8 ≤ 2x

4 ≤ x

Another solution of the inequality is determined as;

3x – 6 ≤ 12

3x ≤ 12 + 6

3x ≤ 18

x ≤ 18/3

x ≤ 6

The solution = 4 ≤ x ≤ 6

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The complete question is below:

Which best describes the solution set of the compound inequality below?

2 + x ≤ 3x – 6 ≤ 12

a: 4 ≤ x ≤ 9

b: 4 ≤ x ≤ 6

c: –2 ≤ x ≤ 2

d: –2 ≤ x ≤ 3

Answer:

To solve the problem, we can use the formula:

Total swim time = (time swimming downstream) + (time swimming upstream)

Let's call the speed of the river's current "c". When swimming downstream, the participant's effective speed is 2 + c miles per hour. When swimming upstream, the effective speed is 2 - c miles per hour.

Using the formula above and plugging in the given values, we get:

1.25 = (1.2 / (2 + c)) + (1.2 / (2 - c))

Simplifying this equation requires some algebraic manipulation, but we can eventually arrive at:

c^2 - 1.44 = 0

Solving for c gives us:

c = ±1.2

Since the participant is swimming both downstream and upstream, we know that the current must be flowing in one direction only. Therefore, we take only the positive solution:

The river's current is 1.2 miles per hour.

The equation for the ellipse is x²/625 + y²/400 = 1

To write an equation for an ellipse centered at the origin, which has foci at (0,±15) and vertices at (0,±25),

we use the formula:

x²/a²+y²/b²=1

where a represents the distance from the center to the vertex and c is the distance from the center to the focus.

The distance from the center to the foci is 15 and the distance from the center to the vertices is 25.

The center is located at the origin which means (h, k) = (0, 0).

Thus, a=25, c=15

Since c is the distance from the center to the focus, then

b² = a² − c²

where a = 25 and c = 15.

Substituting in the formula:

b2 = 25² − 15²

b2 = 400

Thus, the equation for the ellipse is:

x²/625 + y²/400 = 1

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The antiderivative of the original expression, with a constant of integration c is (1/7) * e^(7x-1) / (-6(7x)^6) + c

We want to compute the antiderivative of the expression 7ex − 1 / (7x)7 dx. To do so, we can use the formula for integration by substitution, which states that if we have an integrand of the form f(g(x))g'(x), we can substitute u = g(x) and rewrite the integral in terms of u and du/dx. This allows us to simplify the integral and hopefully make it easier to solve.

So let's apply this formula to the given expression. We notice that we have an exponential function, which suggests that we should try to let u be the exponent. Specifically, we can let u = 7x, so that we have:

u = 7x

du/dx = 7

dx = du/7

Now, we can substitute these expressions for u and dx into the integral:

∫ 7ex−1 / (7x)7 dx

= ∫ 7eu−1 / (7u/7)7 * (du/7) (using the substitutions above)

= (1/7) ∫ e^(u-1)/u^7 du

We can simplify the integral a bit further by using the formula for the antiderivative of e^x, which is simply e^x + c. In this case, we have e^(u-1) in the integrand, so we can write:

(1/7) ∫ e^(u-1)/u^7 du

= (1/7) * e^(u-1) / (-6u^6) + c

Now we can substitute back in our original variable, x, to obtain the final antiderivative:

= (1/7) * e^(7x-1) / (-6(7x)^6) + c

And that's it! This is the antiderivative of the original expression, with a constant of integration c.

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The amount for polishing the triangular tiles at rate of 75 paise cm² is 3306 rupees.

Given data ,

To calculate the area of each triangular tile, we can use Heron's formula, which is based on the lengths of the triangle's sides.

Heron's formula states that for a triangle with side lengths a, b, and c, the area (A) can be calculated as:

A = √(s(s - a)(s - b)(s - c))

where s is the semi perimeter of the triangle given by:

s = (a + b + c) / 2

In this case, the sides of each triangular tile are 9 cm, 28 cm, and 35 cm.

Calculating the semi perimeter:

s = (9 + 28 + 35) / 2

s = 72 / 2

s = 36 cm

Calculating the area using Heron's formula:

A = √(36(36 - 9)(36 - 28)(36 - 35))

A = √(36 * 27 * 8 * 1)

A = √(7776)

A ≈ 88.18 cm²

Since there are 50 triangular tiles, the total area of the floor is approximately ,

50 x 88.18 = 4409 cm².

To calculate the cost of polishing the tiles at a rate of 75 paise (0.75 rupees) per cm², we multiply the total area by the rate:

Cost = 4408 cm² x 0.75 rupees/cm²

Cost ≈ 3306 rupees

Hence , the rough estimate for polishing the tiles would be 3306 rupees

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The measure of angle m∠VRX in the cyclic quadrilateral is equal to 71°

The sum of the opposite angles of a cyclic quadrilateral is equal to 180°, so we solve for the angle m∠VRX of the quadrilateral WXRV as follows:

53x + 3 + 36x - 2 = 180°

89x + 2 = 180°

89x = 180° - 2 {collect like terms}

89x = 178°

x = 178°/89 {divide through by 89}

x = 2

m∠VRX = 36(2) - 2

m∠VRX = 71°

Therefore, the measure of angle m∠VRX in the cyclic quadrilateral is equal to 71°

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The power series expansion for () =[tex]∫x^3ln(1+x) dx centered at x=0 is +∑((-1)^n*x^(n+4))/(n(n+4)).[/tex]

The power series expansion of the indefinite integral ∫x^3ln(1+x) dx, centered at x=0, is given by ∑((-1)^n*x^(n+4))/(n(n+4)), where the summation index starts from n=1 to infinity.

The first 5 nonzero terms of the power series are: -(x)^5/5 + x^6/12 - x^7/21 + x^8/32 - x^9/45. The open interval of convergence for this power series is (-1, 1). This means that the power series representation is valid for all x values between -1 and 1, inclusive.

It's important to note that the convergence at the endpoints of the interval should be checked separately. In summary, the power series expansion provides an approximation of the indefinite integral ∫x^3ln(1+x) dx within the interval (-1, 1).

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Answer:

B

Step-by-step explanation:

7/8 is the same as 7 times one eighth or 7 divided by 8

The solutuion to the given differntial equation is: f(t) = -1/4 e^(2t) + t e^(2t) + 3/4 sin(t)

ℒ{f(t)}(s) = 1/(s^2 - 4s + 5)

We can factor the denominator of the fraction to obtain:

s^2 - 4s + 5 = (s - 2)^2 + 1

Using the partial fraction decomposition, we can write:

1/(s^2 - 4s + 5) = A/(s - 2) + B/(s - 2)^2 + C/(s^2 + 1)

Multiplying both sides by the denominator (s^2 - 4s + 5), we get:

1 = A(s - 2)(s^2 + 1) + B(s^2 + 1) + C(s - 2)^2

Setting s = 2, we get:

1 = B

Setting s = 0, we get:

1 = A(2)(1) + B(1) + C(2)^2

1 = 2A + B + 4C

Setting s = 1, we get:

1 = A(-1)(2) + B(1) + C(1 - 2)^2

1 = -2A + B + C

Solving this system of equations, we get:

A = -1/4

B = 1

C = 3/4

Therefore,

1/(s^2 - 4s + 5) = -1/4/(s - 2) + 1/(s - 2)^2 + 3/4/(s^2 + 1)

Taking the inverse Laplace transform of both sides, we get:

f(t) = -1/4 e^(2t) + t e^(2t) + 3/4 sin(t)

Therefore, the solution to the given differential equation is:

f(t) = -1/4 e^(2t) + t e^(2t) + 3/4 sin(t)

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The orthonormal basis for W is {u_1, u_2, {1, 0, -2}}.

To find an orthonormal basis for W, we first need to normalize the given vectors v_1 and v_2 by dividing each by their magnitude.

The magnitude of v_1 is sqrt(3^2 + (-5)^2 + 6^2) = sqrt(70), so the normalized vector u_1 is (3/sqrt(70), -5/sqrt(70), 6/sqrt(70)).

Similarly, the magnitude of v_2 is sqrt((3/2)² + (9/2)² + 3^2) = 3sqrt(2), so the normalized vector u_2 is (3/2sqrt(2), 9/2sqrt(2), 3/sqrt(2)).

Now, to check if u_1 and u_2 are orthogonal, we take their dot product, which is (3/sqrt(70))*(3/2sqrt(2)) + (-5/sqrt(70))*(9/2sqrt(2)) + (6/sqrt(70))*(3/sqrt(2)) = 0. Therefore, u_1 and u_2 are indeed orthogonal.

Finally, we can verify that the vector {1, 0, -2} is also orthogonal to both u_1 and u_2.

Thus, the orthonormal basis for W is {u_1, u_2, {1, 0, -2}}.

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The missing digit (x) in the pattern is 3 in the second column and 4 in the fourth row. The completed pattern is as follows:

3 2 4 8

7 2 1 3

8 4 3 5

4 3 6 9

To find the missing digit (x) in the given pattern, let's examine the columns and rows to identify any patterns.

Looking at the columns, we can see that the digits in the second column are increasing by 1 each time: 2, 4, x, 3. Therefore, the missing digit (x) must be 2 + 1 = 3.

Similarly, observing the rows, we notice that the digits in the fourth row are decreasing by 1 each time: 8, 5, x, 9. Thus, the missing digit (x) must be 5 - 1 = 4.

Therefore, the missing digit (x) in the pattern is 3 in the second column and 4 in the fourth row. The completed pattern is as follows:

3 2 4 8

7 2 1 3

8 4 3 5

4 3 6 9

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The point (180, -19) is on the terminal side of the angle θ, the exact values of the trigonometric functions are sin(θ) = -19/181, cos(θ) = 180/181, and tan(θ) = -19/180.

Since the point (180, -19) is on the terminal side of the angle θ, we can calculate the trigonometric functions using the coordinates.
First, find the distance from the origin to the point (180, -19). This distance will represent the hypotenuse (r) of the right triangle formed by the terminal side. Use the Pythagorean theorem:
r = √(x^2 + y^2) = √(180^2 + (-19)^2) = √(32400 + 361) = √(32761) = 181
Now that we have the hypotenuse (r), we can find the exact values of the trigonometric functions for the angle θ using the coordinates:
sin(θ) = y/r = -19/181
cos(θ) = x/r = 180/181
tan(θ) = y/x = -19/180
So, given that the point (180, -19) is on the terminal side of the angle θ, the exact values of the trigonometric functions are sin(θ) = -19/181, cos(θ) = 180/181, and tan(θ) = -19/180.

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Answer:

$5.23

Step-by-step explanation:

Another way to write the tax rate is 7.75% or as a decimal 0.0775.

So 4.85 x .0775 = 0.375875 ===>>> that's the amt of tax you'll pay. Now add that to the cost of the ticket.

4.85 + 0.375875 = 5.225875 which rounds to approx $5.23.

Rational numbers are indeed closed under the operations of addition, subtraction, and multiplication is true.

We have,

A rational number is any number that can be expressed as a ratio of two integers, where the denominator is not equal to zero.

The set of rational numbers is closed under the operations of addition, subtraction, and multiplication.

This means that if we take any two rational numbers and add them, subtract them, or multiply them together, the result will always be another rational number.

To see why this is true,

Consider two rational numbers a/b and c/d, where a, b, c, and d are integers and b and d are not equal to zero.

To show that rational numbers are closed under addition, we can add the two rational numbers as follows:

a/b + c/d = (ad + bc) / bd

Since a, b, c, and d are all integers, ad + bc is also an integer.

Also, since b and d are not equal to zero, bd is also not equal to zero.

And,

(ad + bc) / bd is a ratio of two integers, where the denominator is not equal to zero.

This means that it is a rational number.

To show that rational numbers are closed under subtraction, we can subtract the two rational numbers as follows:

a/b - c/d = (ad - bc) / bd

Again, since a, b, c, and d are all integers, ad - bc is also an integer, and bd is not equal to zero.

Therefore, (ad - bc) / bd is a rational number.

Finally, to show that rational numbers are closed under multiplication, we can multiply the two rational numbers as follows:

(a/b) x (c/d) = (ac) / (bd)

Once again, ac and bd are integers, and since b and d are not equal to zero, bd is also not equal to zero.

Therefore, (ac) / (bd) is a rational number.

Thus,

Rational numbers are indeed closed under the operations of addition, subtraction, and multiplication.

Learn more about rational numbers here:

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The scientist descends from 83 feet below sea level to 151 feet below sea level, a change in depth of 151 - 83 = 68 feet. This change occurs over a time of 5 seconds.

The rate of change in depth, or the speed at which the submarine is descending, is given by the ratio of the change in depth to the time taken:

Rate of change in depth = (final depth - initial depth) / time taken

Rate of change in depth = (151 ft - 83 ft) / 5 s

Rate of change in depth = 13.6 ft/s (rounded to one decimal place)

Therefore, the rate of change in the submarine's elevation is 13.6 feet per second.