in a class in which the final course grade depends entirely on the average of four equally weighted 100-point tests, brad has scored 87 , 89 , and 78 on the first three. what range of scores on the fourth test will give brad a c for the semester (an average between 70 and 79 , inclusive)?

Answer:

a) The perimeter of the room is the sum of the lengths of all four sides. The length of two opposite sides is 4x + 3, and the length of the other two opposite sides is 3x. Therefore, the perimeter is:

P = 2(4x + 3) + 2(3x) = 14x + 6

b) The area of the room is the product of the length, width, and height. The length is 4x + 3, the width is 3x, and the height is 3x. Therefore, the area is:

A = (4x + 3)(3x)(3x) = 27x^2 + 12x

c) If both the length and width are doubled, the new dimensions are 2(4x + 3) = 8x + 6 for the length and 2(3x) = 6x for the width.

a) The new perimeter is the sum of the lengths of all four sides:

P' = 2(8x + 6) + 2(6x) = 28x + 12

b) The new area is the product of the length, width, and height:

A' = (8x + 6)(6x)(3x) = 144x^2 + 72x

d) The new perimeter is not twice the original perimeter because:

P' = 28x + 12

2P = 28x + 12 + 28x + 12 = 56x + 24

Therefore, 2P is not equal to P', so doubling the length and width does not double the perimeter.

e) The new area is not twice the original area because:

A' = 144x^2 + 72x

2A = 2(27x^2 + 12x) = 54x^2 + 24x

Therefore, 2A is not equal to A', so doubling the length and width does not double the area.

answer

6 divided by 54 is equal to 9

therefore

answer = d=9

passenger on the train spends approximately 4.65 seconds in the tunnel.

First, we need to convert the speed of the train from km/h to m/s (meters per second) since the length of the tunnel is given in meters. We can do this by dividing the speed in km/h by 3.6, which is the conversion factor from km/h to m/s:

Speed of the train = 120 km/h = (120/3.6) m/s = 33.33 m/s

Next, we can use the formula for time:

time = distance ÷ speed

where distance is the length of the tunnel, and speed is the speed of the train.

Plugging in the given values, we get:

time = 155 m ÷ 33.33 m/s ≈ 4.65 s

Therefore, a passenger on the train spends approximately 4.65 seconds in the tunnel.

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The probability of a cat living more than 16 years can be estimated using the normal distribution. This can be calculated using the following equation: P(X>16) = 1-P(X<16) = 1- Φ((16-12)/2) = 0.1587. This means that the probability of a cat living more than 16 years is approximately 15.87%.

The normal distribution is a continuous probability distribution often used to represent real-world phenomena, such as the lifespan of cats. The distribution is characterized by two parameters, the mean and the standard deviation. The mean is the average value of the data, and the standard deviation is a measure of how spread out the data is around the mean.

To calculate the probability of a cat living more than 16 years, we need to find the cumulative probability of a value less than 16 years. This is done using the normal cumulative probability distribution. We subtract the mean (12 years) from the desired value (16 years) and divide the result by the standard deviation (2 years). We then use this value to calculate the cumulative probability using the cumulative probability function (Φ). The result is 0.1587, meaning that the probability of a cat living more than 16 years is approximately 15.87%.

In conclusion, the probability of a cat living more than 16 years is approximately 15.87%.

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ANSWERS:
A ) x^2 + 5/6x + 25/144 = (x + 5/12)^2

B ) x^2 - 11x + 121/4 = (x - 11/2)^2

EXPLANATION:

a. To complete the square for the equation x^2 + 5/6x + ___,

first divide the coefficient of the linear term (5/6) by 2,

which gives you 5/12.

Then, square the result:

(5/12)^2 = 25/144.

So, the equation becomes:
x^2 + 5/6x + 25/144 = (x + 5/12)^2

b. To complete the square for the equation x^2 - 11x + ___,

first divide the coefficient of the linear term (-11) by 2,

which gives you -11/2.

Then, square the result:

(-11/2)^2 = 121/4.

So, the equation becomes:

x^2 - 11x + 121/4 = (x - 11/2)^2

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I used desmos to graph the equations and this is what I got. Let me know if I've done a typo.

The constant (k) in this inverse variation y = 400/x is 400.

The correct answer choice is option D.

Inverse variation refers to the relationship that exists between two variables, such that the increase in the value of one variable decreases the value of the other variable.

It is written as;

y = k/x

Where,

k = constant of proportionality

x and y = the given variables

So,

y = 400/x

Therefore, it can be concluded that the constant of the inverse variation is 400

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Answer:

Step-by-step explanation:

To find g(4), we substitute x = 4 into the expression for g(x):

g(4) = -3(4) - 4 = -12 - 4 = -16

To find g(4) + 8, we add 8 to the value we just found for g(4):

g(4) + 8 = -16 + 8 = -8

Therefore, g(4) + 8 = -8.

The vertex of the parabola is approximately (7/32, 17.2), which represents the highest point the rock reaches during its flight.

A parabola is a symmetrical, U-shaped curve that is formed by the graph of a quadratic function. The equation of a parabola in standard form is y = ax² + bx + c, where "a", "b", and "c" are constants, and "x" and "y" are variables.

a. To evaluate h(0), we substitute t=0 in the equation:

h(0) = 15 + 7(0) - 16(0)² = 15

This means that at the instant the boy throws the rock (t=0), the height of the rock is 15 feet above the ground.

b. To estimate the time when the rock hits the ground, we need to find the value of t when h(t) = 0. We can solve the equation 15 + 7t - 16t² = 0 for t, using the quadratic formula:

t = (-7 ± √(7² - 4(-16)(15))) / (2(-16))

t ≈ 1.28 s or t ≈ 1.97 s

This means that the rock will hit the ground approximately 1.28 seconds or 1.97 seconds after it is thrown.

c. The equation h(1) = 6 means that one second after the rock is thrown, its height above the ground is 6 feet.

d. The vertex of the parabola h(t) = 15 + 7t - 16t² can be found by using the formula t = -b/2a, where a=-16 and b=7.

t = -7 / (2(-16)) = 7/32

Substituting t=7/32 into the equation, we get:

h(7/32) = 15 + 7(7/32) - 16(7/32)² ≈ 17.2

Therefore, the vertex of the parabola is approximately (7/32, 17.2), which represents the highest point the rock reaches during its flight.

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Answer:76904685 ways

please give brainliest

The answer of the given question based on the supplementary angle is  the two angles are 58° degrees and 122° degrees.

An angle is a geometric figure that is formed by two rays or lines that share a common endpoint, called the vertex. The rays or lines are called  sides or arms of  angle. Angles are typically measured in the degrees or the radians.

The measure of an angle is determined by the amount of rotation needed to bring one of its sides into coincidence with the other side. A full rotation is 360° degrees, so an angle that is half of a full rotation is 180 degrees, an angle that is a quarter of a full rotation is 90° degrees, and so on.

Let's call the two angles "x" and "y". We know that they are supplementary, which means that their sum is 180° degrees:

x + y = 180

We also know that one angle (let's say "x") is two times the sum of the other angle (y) and 3:

x = 2(y + 3)

Now we can substitute the second equation into the first equation to eliminate "x":

(2(y + 3)) + y = 180

Simplifying the equation, we get:

3y + 6 = 180

Subtracting 6 from both sides, we get:

3y = 174

Dividing both sides by 3, we get:

y = 58

Now that we know "y", we can substitute it back into the equation for "x" to find its value:

x = 2(y + 3) = 2(58 + 3) = 122

Therefore, the two angles are 58° degrees and 122° degrees.

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Answer:

B.

Step-by-step explanation:

I just took the test

Answer:

[tex]y-3=-\frac{3}{2}(x-2)[/tex]

Step-by-step explanation:

In order to find an equation that is parallel, it must have the same slope. This means the y intercept could literally be anything.

By equation of the line, we can write it in point slope form

[tex]y-y1=m(x-x1)[/tex]

where y1 and x1 are points on the coordinate plane and m is the slope.

We are already given the slope, so we just plug in the numbers.

[tex]y-3=-\frac{3}{2}(x-2)[/tex]

Answer:

false, 216° turns 3/5 in a 360° rotation

a) an = 3n-1 · 2

b) an = 2·n

c) an = 5·n + 8

d) an = 4n-1 · 1

Let's dive deeper into the details below.
(a) The sequence 2, 5, 10, 17, 26 is a geometric sequence with common ratio 3 and a1 = 2. Therefore, the closed formula is an = 3n-1 · 2.

(b) The sequence 0, 2, 5, 9, 14 is an arithmetic sequence with common difference 2 and a1 = 0. Therefore, the closed formula is an = 2·n.

(c) The sequence 8, 12, 17, 23 is an arithmetic sequence with common difference 5 and a1 = 8. Therefore, the closed formula is an = 5·n + 8.

(d) The sequence 1, 5, 23, 119 is a geometric sequence with common ratio 4 and a1 = 1. Therefore, the closed formula is an = 4n-1 · 1.

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(a) To find P(0 < Z < 2.74), you'll want to look up the z-score for 2.74 in a standard normal table or use a calculator with a built-in normal distribution function. The probability is the area under the curve between 0 and 2.74.

(b) To find P(0 < Z < 1), you'll look up the z-score for 1 in a standard normal table or use a calculator. The probability is the area under the curve between 0 and 1.

(c) To find P(-2.40 < Z < 0), you'll look up the z-score for -2.40 in a standard normal table or use a calculator. The probability is the area under the curve between -2.40 and 0.

(d) To find P(-2.40 < Z < 2.40), you can first calculate the probability for P(-2.40 < Z < 0) and P(0 < Z < 2.40), and then sum the two probabilities.

(e) To find P(Z > 1.63), look up the z-score for 1.63 in a standard normal table or use a calculator. The probability is the area under the curve to the right of 1.63.

(f) To find P(Z < -1.74), look up the z-score for -1.74 in a standard normal table or use a calculator. The probability is the area under the curve to the left of -1.74.

(g) To find P(-1.4 < Z < 2.00), first look up the z-scores for -1.4 and 2.00 in a standard normal table or use a calculator. Subtract the smaller probability from the larger probability to find the area under the curve between these two values.

(h) To find P(1.63 < Z < 2.50), first look up the z-scores for 1.63 and 2.50 in a standard normal table or use a calculator. Subtract the smaller probability from the larger probability to find the area under the curve between these two values.

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The relationship between the mean and median depends on the shape of the distribution of the data, therefore correct options are

(a) The mean is approximately the same as the median

(b) The mean is greater than the median

(c)  The mean is less than the median.

The relationship between the mean and the median depends on the shape of the distribution of the data. In a symmetric distribution, the mean and median will be approximately the same. In a skewed distribution, the mean will be pulled in the direction of the skew, and the median will be a better representation of the "typical" value.

If the distribution is symmetrical (i.e., evenly distributed around the center), the mean and median will be approximately the same.

If the distribution is positively skewed (i.e., has a long tail on the right side), the mean will be greater than the median.

If the distribution is negatively skewed (i.e., has a long tail on the left side), the mean will be less than the median.

Therefore, correct options are

(a) The mean is approximately the same as the median

(b) The mean is greater than the median

(c)  The mean is less than the median.

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The probability of selecting 8 female students from a sample of 8 students from a student body with 60% female students is 0.2187, or 21.87%.

The probability of selecting a sample of 8 students from a student body of 60% female students is calculated using binomial probability. The binomial probability formula is used to calculate the probability of a certain number of successes in a certain number of independent trials. In this case, the probability of selecting 8 students, with 60% being female students, can be calculated using the binomial probability formula.

The probability can be calculated using the following equation:
[tex]P(x=8) = (n!/((n-x)!x!)) * p^x * q^{(n-x)}[/tex]

Where:

In this case, n = 8, x = 8, p = 0.6, and q = 0.4. Plugging these values into the equation gives us a probability of 0.2187. This means that there is a 21.87% chance of selecting 8 female students out of a sample of 8 students from a student body with 60% female students.

It is important to remember that binomial probability is only used when there are two possible outcomes in each trial (i.e. success or failure). Additionally, it is important to remember that the equation only applies when the trials are independent of each other.

In conclusion, the probability of selecting 8 female students from a sample of 8 students from a student body with 60% female students is 0.2187, or 21.87%.

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The probability that a randomly chosen college student will spend between $300 and $400 on clothing in a year is approximately 0.6645 or 66.45%.

To solve this problem, we need to standardize the given range of values using the z-score formula:

z = (x - μ) / σ

where x is the value of interest, μ is the mean, and σ is the standard deviation. For x = 300:

z = (300 - 310) / 50 = -0.2

For x = 400:

z = (400 - 310) / 50 = 1.8

Using a standard normal distribution table or calculator, we can find the probability of the z-score being between -0.2 and 1.8:

P(-0.2 ≤ z ≤ 1.8) = 0.6645

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The mean of the differences was 1.33 and the standard deviation of those differences was 2.90. The test statistic for this procedure is 1.90. The correct option is D.

Makers of generic drugs are required to show that their generic drugs do not differ significantly from the "reference" or brand name drugs that they imitate. One aspect in which the generic drugs might differ is their extent of absorption in the blood. Twelve subjects were available for the study. Six were randomly selected to receive the generic drug first and then, after a washout period, receive the "reference" drug. The remaining six received the "reference" drug first, followed by the generic drug after the washout period. Assume that all conditions are met.

The mean of the differences was 1.33 and the standard deviation of those differences was 2.90.

A t-test statistic for a paired sample is to be calculated to find out whether or not there is a statistically significant difference between the two treatments. The formula for a t-test statistic is given below:

t= x¯d/sd / √n

where x¯d is the mean difference,

sd is the standard deviation of the differences, and

n is the number of subjects.

Using the given values, we can substitute in the formula and solve for t as follows:

t=1.33/2.90 / √12t=1.90

Hence, the test statistic for this procedure is 1.90.

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Answer: x is equal to 1

Step-by-step explanation:

Answer:

Carbon compounds are defined as chemical substances containing carbon i'd say.

The lower quartile of the given set of numbers 4, 6, 7, 8, 10, 12, 20 is 6. So, correct option is B.

To find the lower quartile of a set of numbers, we first need to arrange them in ascending order. The given numbers are: 4, 6, 7, 8, 10, 12, 20.

Next, we divide the data set into four equal parts. The lower quartile is the median of the lower half of the data set. In this case, the lower half is 4, 6, and 7.

To determine the median of the lower half, we need to find the middle value. Since we have an odd number of data points in the lower half, the middle value is the single value between the two extremes. In this case, the median is 6.

This corresponds to option (b) in the given choices: 6.

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Answer: 3x-2x or (3x)-(2x)

Write an expression that best represents the difference between triple and double a number?

Step-by-step explanation: HOPE THIS HELPS!

Answer:

3x-2x

Step-by-step explanation:

I hope you this is it

280 dogs in all of the city's animal shelters are puppies. The solution has been obtained by using ratios.

What is ratio?

The ratio between two amounts of the same unit can be used to determine how much of one quantity is included in the other.

We are given that different animal shelters in a city shows that 10 of the 70 dogs are puppies and the city's animal shelters collectively house 1,960 dogs each year.

So, from this we get the ratio as

⇒ [tex]\frac{10}{70}[/tex] = [tex]\frac{x}{1960}[/tex]

Now, by cross multiplying, we get

⇒ 19,600 = 70x

⇒ x = 280

Hence, 280 dogs in all of the city's animal shelters are puppies.

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The equation of the line is 9x+8y + 19 = 0 and 5x - 4y+ 19 = 0 According to the given graphs, these are the equations of the graph.

Consider two points on the blue line.

The points are (5, -8) and ( -3,1 ).

Equation of the blue line is:

y - 1 = [tex]\frac{-8-1}{5+3} (x+3)[/tex]

8 (y - 1) = -9 ( x + 3)

8y - 8 = -9x -27

9x + 8y + 19 = 0

Therefore, the Equation of the blue line is 9x + 8y + 19 = 0.

Consider two points on the red line.

The points are (-3, 1) and ( 1,6 ).

Equation of the red line is:

y - 1 = [tex]\frac{6-1}{1+3} (x+3)[/tex]

4 (y - 1) = 5 (x + 3)

4y - 4 = 5x + 15

5x - 4y+ 19 = 0

Therefore, the Equation of the red line is 5x - 4y+ 19 = 0.

Hence, the equations for the given blue and red lines are completed.

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Part a: Expression for conventional account: $(5000-x) at 5%pa.

Part b: polynomial model: T =  5250  -  0.01x

Part c: Sum of investments in retirement account: T= $5245.

When they need to raise money, governments and businesses issue bonds.

a. Create an expression to show how much money is invested in the conventional account.

Back $(5000-x) at 5%pa

b. Construct a polynomial model in its simplest form to represent the entire sum of investments made by T. Kent after a year (possibility: thus every account has A + iA dollars, in Which a is the account's initial balance and I is the interest rate).

The bond will increase to after a year to : x + 0.04x

= x(1+0.04)

= 1.04x   ...eq 1

So, after the time of one year this traditional account growth will be-

(5000-x) + 0.05(5000-x)

= 5000 - x  + 0.05*5000  -  0.05x

= 5000  -  x  + 250  -  0.05x

= 5250  -  1.05x  ..eq 2

From eq 1 and eq 2

T = 1.04x + 5250  -  1.05x

T =  5250  -  0.01x

c. If Kent invested $500 in bonds, how much will he have in the retirement account in a year?

x=500

T= 5250  - 0.01*500

T= 5250 - 5

T= $5245

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The experimental probability of landing on blue is found by dividing the number of times blue was landed on by the total number of spins.

Experimental probability of landing on blue = Number of times blue was landed on / Total number of spins

Probability is a measure of the likelihood or chance of an event occurring. It is a number between 0 and 1, where 0 means the event is impossible and 1 means the event is certain. Probability is calculated by dividing the number of favorable outcomes by the total number of possible outcomes.

Therefore, the experimental probability of landing on blue is 4/9 or approximately 0.444 or 44.4% (rounded to the nearest tenth or percentage).

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