The correlation coefficient for the given data set is 0.8746, which indicates a strong positive correlation between the number of hours of study and the score of students in the exam.
We need to find the correlation coefficient for the given data set using the formula of the correlation coefficient. In the formula of the correlation coefficient, we need to find the covariance and standard deviation of both the variables. But in this given data set, we have only one variable. Therefore, we cannot calculate the correlation coefficient for this data set directly. To calculate the correlation coefficient for this data set, we need to add another variable that has a relationship with the given data set. Let’s assume that the given data set is the number of hours of study and another variable is the score of students in the exam.
Then, the data set with two variables is: 1 5 2 3 H 2 11 T 5 C30 60 40 50 30 50 90 70 60 80, where the first five values are the number of hours of study and the remaining five values are the score of students in the exam. Now, we can calculate the correlation coefficient of these two variables using the formula of the correlation coefficient:
ρ = n∑XY - (∑X)(∑Y) / sqrt((n∑X^2 - (∑X)^2)(n∑Y^2 - (∑Y)^2)), where, X = number of hours of study, Y = score of students in the exam, n = number of pairs of observations of X and Y∑XY = sum of the products of paired observations of X and Y∑X = sum of observations of X∑Y = sum of observations of Y∑X^2 = sum of the squared observations of X∑Y^2 = sum of the squared observations of Y. Now, we will find the values of these variables and put them in the above formula:
∑XY = (1×30) + (5×60) + (2×40) + (3×50) + (2×30) + (11×50) + (5×90) + (1×70) + (2×60) + (3×80)= 1490∑X = 1 + 5 + 2 + 3 + 2 + 11 + 5 + 1 + 2 + 3= 35∑Y = 30 + 60 + 40 + 50 + 30 + 50 + 90 + 70 + 60 + 80= 560∑X^2 = 1^2 + 5^2 + 2^2 + 3^2 + 2^2 + 11^2 + 5^2 + 1^2 + 2^2 + 3^2= 153∑Y^2 = 30^2 + 60^2 + 40^2 + 50^2 + 30^2 + 50^2 + 90^2 + 70^2 + 60^2 + 80^2= 30100n = 10.
Now, we will put these values in the formula of the correlation coefficient:
ρ = n∑XY - (∑X)(∑Y) / sqrt ((n∑X^2 - (∑X)^2)(n∑Y^2 - (∑Y)^2)) = (10×1490) - (35×560) / sqrt ((10×153 - 35^2).(10×30100 - 560^2)) = 0.8746. Therefore, the correlation coefficient for the given data set is 0.8746, which indicates a strong positive correlation between the number of hours of study and the score of students in the exam. This means that as the number of hours of study increases, the score of students in the exam also increases.
Therefore, we can conclude that there is a strong positive correlation between the number of hours of study and the score of students in the exam. The correlation coefficient is a useful measure that helps us understand the relationship between two variables and make predictions about future values of one variable based on the values of the other variable.
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The correlation coefficient for the given set is 0.156, and it shows a weak positive correlation between the variables
A correlation coefficient is a quantitative measure of the association between two variables. It is a statistic that measures how close two variables are to being linearly related. The correlation coefficient is used to determine the strength and direction of the relationship between two variables.
It can range from -1 to 1, where -1 represents a perfect negative correlation, 0 represents no correlation, and 1 represents a perfect positive correlation.
The formula for computing the correlation coefficient is:
r = n∑XY - (∑X)(∑Y) / sqrt((n∑X^2 - (∑X)^2)(n∑Y^2 - (∑Y)^2))
Given set of data,
set 1 = {5, 2, 3, 2, 11, 5}.
Let's compute the correlation coefficient using the above formula.
After simplification, we get,
r = 0.156
Therefore, the correlation coefficient for the given set 1 is 0.156.
Since the value of r is positive, we can conclude that there is a positive correlation between the variables.
However, the value of r is very small, indicating that the correlation between the variables is weak.
Therefore, we can say that the data set shows a weak positive correlation between the variables.
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3. Consider the following system: →0.85→0.85→ Determine the probability that the system will operate under each of these conditions: a. The system as shown. (Do not round your intermediate calculations. Round your final answer to 4 decimal places.) b. Each system component has a backup with a probability of .85 and a switch that is 100 percent reliable. (Do not round your intermediate calculations. Round your final answer to 4 decimal places. c. Each system component has a backup with a probability of .85 and a switch that is 90 percent reliable. (Do not round your intermediate calculations. Round your final answer to 4 decimal places.)
a. The probability that the system will operate as shown is approximately 0.6141.
b. Probability ≈ 0.6141The probability remains the same as in the previous case, which is approximately 0.6141.
c. The probability that the system will operate with each component having a backup with a probability of 0.85 and a switch that is 90% reliable is approximately 0.6485.
a. To find the probability that the system will operate as shown, we multiply the probabilities of each component. Since the system is shown to have three components with a probability of 0.85 each, we can calculate:
Probability = 0.85 × 0.85 × 0.85
Probability ≈ 0.6141
The probability that the system will operate as shown is approximately 0.6141.
b. In this case, each system component has a backup with a probability of 0.85 and a switch that is 100% reliable. Since the backup has a probability of 0.85, and the switch is 100% reliable (probability = 1), we can calculate the probability as:
Probability = 0.85 × 0.85 × 0.85
Probability ≈ 0.6141The probability remains the same as in the previous case, which is approximately 0.6141.
c. In this scenario, each system component has a backup with a probability of 0.85, but the switch is 90% reliable (probability = 0.90). We can calculate the probability as:
Probability = 0.85 × 0.90 × 0.85
Probability ≈ 0.6485
The probability that the system will operate with each component having a backup with a probability of 0.85 and a switch that is 90% reliable is approximately 0.6485.
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On the track at school , Suzy ran 1/2 of a lap in 2/3 min. What is the unit rate in minutes per lap?
Given:
Suzy ran 1/2 of a lap in 2/3 minutes.
The unit rate in minutes per lap is,
\(\frac{\frac{2}{3}}{\frac{1}{2}}=\frac{2}{3}\cdot2=\frac{4}{3}\text{ minutes per lap}\)Answer: 4/3 minute per lap.
Question
56 is 80% of what number? Use the percent equation.
56 is 80% of what number?
Formula - \(\dfrac{Number\times100}{Percent}\)
______________________
\(\dfrac{56\times100}{80} =\dfrac{5600}{80}=\fbox{70}\)
A local shoe store buys shoes at a wholesale price and then marks them up 80% to calculate the retail price. The wholesale price varies, depending on the quantity of shoes purchased. (2 points)
Quantity
0-20 pairs
21-40 pairs
41-60 pairs
61-80 pairs
81 or more pairs
Wholesale Price
(per pair)
$25.00 each
$23.00 each
$21.00 each
$19.00 each
$17.00 each
What is the quantity of pairs and how much are they each pair??
Answer:
They buy at wholesale and sell at an 80% markup. The retail prices are;
0 - 20 pairs.
= 25 * 1.80
= $45.00
21 - 40 pairs
= 23 * 1.80
= $41.40
41 - 60 pairs
= 21 * 1.80
= $37.80
61 - 80 pairs
= 19 * 1.80
= $34.20
81 or more pairs
= 17 * 1.80
= $30.60
What is the center of the circle with the equation (x+4)^2 + (y - 2)^2 = 16? a (-4, -2) b (4,2) c (-4, 2) d (4, -2)
Answer:
C) (-4, 2)
Step-by-step explanation:
Answer:
The center is ( -4,2) and the radius is 4
Step-by-step explanation:
The equation of a circle can be written as
( x-h) ^2 + ( y-k) ^2 = r^2 where ( h,k) is the center and r is the radius
(x+4)^2 + (y - 2)^2 = 16
(x- -4)^2 + (y - 2)^2 = 4^2
The center is ( -4,2) and the radius is 4
A town has a population of 2000 and grows at 4.5% every year. To the nearest
tenth of a year, how long will it be until the population will reach 3900?
What is the slope and y-intercept of the function represented by the table
slope =
y-intercept =
what is size for tv?
The size for a TV is determined as the diagonal length of the Television.
The Televisions that we see in our daily life are mostly of the rectangular shape.
A rectangular shape is a shape that has 4 sides in it, the opposite sides of the rectangular are parallel and equal. Two pairs of equal sides are formed in this type of shape.
If we connect the vertices that are directly opposite to each other than it is known as the diagonal of the rectangle . Often we see that the TV is of 32'' or 64''. This only means that the diagonal length of the TV is 32'' or 64''. This is how we measure the size of the TV.
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Can you list all the real numbers frim 1 through 5? Explain
There is a infinite number of real numbers from 1 through 5
How to determine the count of real numbers from 1 through 5?The range is given as
1 to 5
The set of numbers is given as
Real numbers
Real numbers are any number that are not complex or imaginary numbers
This type of number covers all types of number that are not complex or imaginary numbers and it has an infinite count
Since the numbers cannot be counted, we can conclude that there is a infinite number of real numbers from 1 through 5
Hence, there is a infinite number of real numbers from 1 through 5
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suppose that there exists a constant rate of change between x and y . which of the following statements are true? select all that apply.
The statements that are true when there exists a constant rate of change between x and y are:
1. The graph of the relationship between x and y is a straight line.
2. The slope of the line represents the constant rate of change between x and y.
3. The value of the slope is the same for any two points on the line.
4. The equation that represents the relationship between x and y can be written in the form y = mx + b, where m is the slope and b is the y-intercept.
5. The value of the y-intercept is the y-coordinate of the point where the line crosses the y-axis.
Let's break down each statement:
1. The graph of the relationship between x and y is a straight line:
When there is a constant rate of change between x and y, the graph will be a straight line. This means that the points representing the relationship between x and y will lie on a straight line when plotted on a graph.
2. The slope of the line represents the constant rate of change between x and y:
The slope of a line is a measure of how steep or flat the line is. In this case, when there is a constant rate of change between x and y, the slope of the line will be the same for any two points on the line. It represents the rate at which y changes for every unit change in x.
3. The value of the slope is the same for any two points on the line:
As mentioned earlier, the slope represents the constant rate of change between x and y. Regardless of which two points we choose on the line, the ratio of the change in y to the change in x will always be the same.
4. The equation that represents the relationship between x and y can be written in the form y = mx + b, where m is the slope and b is the y-intercept:
When there is a constant rate of change between x and y, we can express their relationship using an equation in the form y = mx + b. The slope, represented by the variable m, will be the coefficient of x, and the y-intercept, represented by the variable b, will be the value of y when x is equal to 0.
5. The value of the y-intercept is the y-coordinate of the point where the line crosses the y-axis:
The y-intercept is the point where the line representing the relationship between x and y crosses the y-axis. It represents the value of y when x is equal to 0.
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Tell whether the set of ordered pairs {(1, 6), (2, 9), (3, 12), (4, 15)} satisfies a linear function. Explain.
A. No; there is no constant change in x that corresponds to a constant change in y.
B. Yes; there is no constant change in x that corresponds to a constant change in y.
C. No; there is a constant change in x that corresponds to a constant change in y.
D. Yes; there is a constant change in x that corresponds to a constant change in y.
Answer:
D
Step-by-step explanation:
If you put them into a graphing calculator they all align. Have a nice day.
Consider the PDE au(x, t) = 4 d²u(x, t) 2 Ət əx² For each of BCs and ICs, solve the initial value problem. du(π,t) a) BCs: u(0,t)=0 = = 0 and əx IC: u(x,0) = x ANSWER: f(x)= n=1 u(2,t) = 0 and u(0,t)=0 u(x,0)=sin x ANSWER: f(x)=¹1_sin(2 + nx) na n=1 1+ 2 X b) BCs: IC: 8 (2n-1) T n+1 (-1)041 -4(2n-1)²t sin(2-nπ) nπ 1- 2 e sin (2n-1) 2 na sin X 2 -(nn)²t x -X
the solution for the initial value problem is: u(x, t) = sin(sqrt(-λ² * (a / 4)) * x) * exp(-λ² * t) where λ = ± sqrt(-4n² / a), and n is a non-zero integer.
The given partial differential equation is:
au(x, t) = 4 * (d²u(x, t) / dt²) / (dx²)
a) BCs (Boundary Conditions):
We have u(0, t) = 0 and u(π, t) = 0.
IC (Initial Condition):
We have u(x, 0) = x.
To solve this initial value problem, we need to find a function f(x) that satisfies the given boundary conditions and initial condition.
The solution for f(x) can be found using the method of separation of variables. Assuming u(x, t) = X(x) * T(t), we can rewrite the equation as:
X(x) * T'(t) = 4 * X''(x) * T(t) / a
Dividing both sides by X(x) * T(t) gives:
T'(t) / T(t) = 4 * X''(x) / (a * X(x))
Since the left side only depends on t and the right side only depends on x, both sides must be equal to a constant value, which we'll call -λ².
T'(t) / T(t) = -λ²
X''(x) / X(x) = -λ² * (a / 4)
Solving the first equation gives T(t) = C1 * exp(-λ² * t), where C1 is a constant.
Solving the second equation gives X(x) = C2 * sin(sqrt(-λ² * (a / 4)) * x) + C3 * cos(sqrt(-λ² * (a / 4)) * x), where C2 and C3 are constants.
Now, applying the boundary conditions:
1) u(0, t) = 0:
Plugging in x = 0 into the solution X(x) gives C3 * cos(0) = 0, which implies C3 = 0.
2) u(π, t) = 0:
Plugging in x = π into the solution X(x) gives C2 * sin(sqrt(-λ² * (a / 4)) * π) = 0. To satisfy this condition, we need the sine term to be zero, which means sqrt(-λ² * (a / 4)) * π = n * π, where n is an integer. Solving for λ, we get λ = ± sqrt(-4n² / a), where n is a non-zero integer.
Now, let's find the expression for u(x, t) using the initial condition:
u(x, 0) = X(x) * T(0) = x
Plugging in t = 0 and X(x) = C2 * sin(sqrt(-λ² * (a / 4)) * x) into the equation above, we get:
C2 * sin(sqrt(-λ² * (a / 4)) * x) * C1 = x
This implies C2 * C1 = 1, so we can choose C1 = 1 and C2 = 1.
Therefore, the solution for the initial value problem is:
u(x, t) = sin(sqrt(-λ² * (a / 4)) * x) * exp(-λ² * t)
where λ = ± sqrt(-4n² / a), and n is a non-zero integer.
Note: Please double-check the provided equation and ensure the values of a and the given boundary conditions are correctly represented in the equation.
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The Jones family wants to enclose their circular garden with a fence. To the 1 point
nearest meter, what is the minimum length of fencing they need to buy?
Note that radius of garden is 62.5m. User as 3.14.
Answer:
Step-by-step explanation:
We have to find the circumference.
Length of the fence = 2πr
= 2* 3.14 * 62.5
= 392.5
= 393 m
1.6-4.7n+0.23=-4.4n+2.94 Provide step by step please
Answer:
n= 0.121978
Step-by-step explanation:
1.6-4.7n+0.23=-4.4n+2.94
4.7n+1.83=-4.4n+2.94
4.7n=-4.4n+2.94-1.83
4.7n=-4.4n+1.11
4.7n+4.4n=1.11
9.1×n=1.11
n=1.11/9.1
n=0.121978
Answer:
n=-3.7
Step-by-step explanation:
1.6-4.7n+0.23=-4.4n+2.94
-4.7n+1.83=-4.4n+2.94
+4.4n both sides
-0.3n+1.83=2.94
-1.83 both sides
-0.3n=1.11
Divide 3 both sides
n=-3.7
(-9+3i) - (6-4i) find the difference
Answer:
Step-by-step explanation:
please help :( I’m so bad with graphing, anyone know the answer ?
Answer:
B
Step-by-step explanation:
I graphed the inequality on a graphing calc.
per the central limit theorem the standard deviation of the sampling distribution of the sample mean is equal to the population: a. standard deviation divided by n b. standard deviation divided by the square root of n c. mean d. standard deviation
The correct option is D, Per the Central Limit Theorem the mean of the sampling distribution of the sample mean is equal to the population Mean.
The Central Limit Theorem (CLT) is a fundamental concept in probability theory and statistics. It states that if you take repeated random samples of a population, the sample means will follow a normal distribution, regardless of the shape of the population distribution, provided the sample size is large enough. This means that as the sample size increases, the sample mean becomes more and more normally distributed.
The CLT is important because it helps us to understand the properties of large samples, even when the population is not normally distributed. It is used in many areas of research, including social sciences, finance, engineering, and more. The theorem provides a powerful tool for estimating population parameters, such as the mean or variance, and for testing hypotheses about them. It also helps to explain why the normal distribution is so commonly observed in real-world data, and why it is often used as a model for statistical analysis.
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Complete Question:-
Per the Central Limit Theorem the mean of the sampling distribution of the sample mean is equal to the population:
a. Standard deviation divided by n
b. Mean divided by n
c. Standard Deviation divided by the square root of n
d. Mean
Mai had $14.50. She spent $5.25 at the arcade. What is the exact amount of money
Mai has left?
Answer:
nine dollars and 27 cents
Step-by-step explanation:
if u minus 14.50 minus 5.25 u get 9.27 9 dollars and 27 cents
Yw!
Answer:
9.25
Step-by-step explanation:
subtract 5.25 from 14.50
A SCHOOL HAS 320 GIRLS AND 250 BOYS
THE PROBABILITY THAT A GIRL IS LEFT-HANDED IS 0.2
THE PROBABILITY THAT A BOY IS LEFT-HANDED IS 0.1
ESTIMATE THE NUMBER OF LEFT-HANDED STUDENTS IN THE SCHOOL
Answer:
89
Step-by-step explanation:
I just multiplied 320 by 0.2 and then 250 by 0.1 and then added them together. I hope it helps and I'm not sure what method you would use for this but that's mine.
a business owner pays $500 a week for rent.He also pays an employee $16 an hour.If his total weekly expenses are $1,172 ,how many hours did his employee work?
what does it mean when the second derivative equals zero
When the second derivative of a function equals zero, it indicates a possible point of inflection or a critical point where the concavity of the function changes. It is a significant point in the analysis of the function's behavior.
The second derivative of a function measures the rate at which the slope of the function is changing. When the second derivative equals zero at a particular point, it suggests that the function's curvature may change at that point. This means that the function may transition from being concave upward to concave downward, or vice versa.
Mathematically, if the second derivative is zero at a specific point, it is an indication that the function has a possible point of inflection or a critical point. At this point, the function may exhibit a change in concavity or the slope of the tangent line.
Studying the second derivative helps in understanding the overall shape and behavior of a function. It provides insights into the concavity, inflection points, and critical points, which are crucial in calculus and optimization problems.
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When the second derivative of a function equals zero, it indicates a critical point in the function, which can be a maximum, minimum, or an inflection point.
The second derivative of a function measures the rate at which the slope of the function is changing. When the second derivative equals zero, it indicates a critical point in the function. A critical point is a point where the function may have a maximum, minimum, or an inflection point.
To determine the nature of the critical point, further analysis is required. One method is to use the first derivative test. The first derivative test involves examining the sign of the first derivative on either side of the critical point. If the first derivative changes from positive to negative, the critical point is a local maximum. If the first derivative changes from negative to positive, the critical point is a local minimum.
Another method is to use the second derivative test. The second derivative test involves evaluating the sign of the second derivative at the critical point. If the second derivative is positive, the critical point is a local minimum. If the second derivative is negative, the critical point is a local maximum. If the second derivative is zero or undefined, the test is inconclusive.
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I-Ready
Describe Angle Relationships in Triangles - Quiz - Level H
The figure shoys a triangle with unknown angles.
Which equation shows the relationship between the angles in the triangle?
mL1 + mL2 + mL3 = 360°
mL1 + mL2 + mL3 = 180°
mL1 + mL2 = 360° + mL3
mL1 + mL2 = 180° + mL3
The equation that shows the relationship between the angles in the triangle is m∠1 + m∠2 + m∠3 = 180.
What is the relationship between the angles of the triangle?The equation that shows the relationship between the angles in the triangle is determined as follows;
The sum of angles in a triangle is equal to 180 degrees.
So based on this information, the equation that shows the relationship between the angles in the triangle is formulated as;
angle 1 + angle 2 + angle 3 = 180
We can re-write the equation as follows;
m∠1 + m∠2 + m∠3 = 180
Thus, the equation that shows the relationship between the angles in the triangle is the sum of angle 1 plus angle 2 plus angle 3.
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find a power series representation for the function. (give your power series representation centered at x = 0.) f(x) = x 6x2 1
the power series representation of f(x) = x / (6x^2 + 1) centered at x = 0 is:
f(x) = x + 6x^3 + 18x^5 + 108x^7 + ...
To find a power series representation for the function f(x) = x / (6x^2 + 1) centered at x = 0, we can use the concept of geometric series.
First, let's rewrite the denominator as 6x^2 + 1 = 1 + 6x^2.
Now, we can rewrite the function as:
f(x) = x / (1 + 6x^2).
To represent this function as a power series, we need to find a geometric series that matches the form (1 + r)^n, where r is a constant.
Let's rewrite the function as follows:
f(x) = x * (1 + 6x^2)^(-1).
Now, we can use the geometric series formula:
(1 + r)^n = 1 + nr + (n(n-1)/2!) r^2 + (n(n-1)(n-2)/3!) r^3 + ...
Substituting r = -6x^2 and n = -1, we have:
(1 + (-6x^2))^(-1) = 1 + (-1)(-6x^2) + ((-1)(-2)/2!) (-6x^2)^2 + ((-1)(-2)(-3)/3!) (-6x^2)^3 + ...
Simplifying:
(1 - 6x^2)^(-1) = 1 + 6x^2 + (1/2)(6x^2)^2 + (1/6)(6x^2)^3 + ...
We can rewrite this as:
(1 - 6x^2)^(-1) = 1 + 6x^2 + 18x^4 + 108x^6 + ...
Now, we can multiply both sides by x to obtain the power series representation of f(x):
x / (1 + 6x^2) = x (1 - 6x^2)^(-1) = x (1 + 6x^2 + 18x^4 + 108x^6 + ...)
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what is
59.7 + -12,100
Answer:
-12,040.3
Step-by-step explanation:
When you have a + and a - next to each other it becomes a -, so the problem we do is 59.7 -12,100 which comes to -12040.3.
Answer:
-12040.3
Step-by-step explanation:
Why didn't just search it up? Could've saved you points.
Evaluate –x + 3.9 for x = –7.2.
–11.1
11.1
3.3
–3.3
Maya is hiking down a mountain after one hours she is at 500 feet elevation and after three hours she is at 300 feet elevation
Answer:
Maya is hiking down at a speed of 100 feet per hour.
Step-by-step explanation:
Given that Maya is hiking down a mountain, and after one hours she is at 500 feet elevation while after three hours she is at 300 feet elevation, to determine the speed at which Maya is hiking down the following calculation must be performed:
3-1 = 2
500-300 = 200
200/2 = 100
Thus, Maya is hiking down at a speed of 100 feet per hour.
A train traveled 300 miles in 4 and 1/2 hours how fast did the train travel per hour?
Answer: 66\(\frac{6}{9}\) miles per hour
Step-by-step explanation:
300 miles * 1 hour/4 1/2 hours =
300 miles * 1 hour/(4+1/2) hours =
300 miles * 1 * 2 hour/((4+1/2) * 2) hours =
300 miles * 2 hours/(8+1) hours =
300 miles * 2 hours/9 hours =
300 * 2/9=
600/9=
(594+6)/9=
594/9 + 6/9=
66+6/9=66 6/9 miles per hour
The height of a ball in the air off the ground in meters, t seconds after it is thrown, is given by the equation s(t)=-4.9t^(2)+10t+16 Approximately at what times is the ball lower than 15 meters off the ground?
In quadratic equation, The ball is lower than 15 meters at approximately 0.41 seconds and 1.94 seconds after it is thrown.
Given equation is s(t) = -4.9t² + 10t + 16.
The ball is below the height of 15m off the ground.
Therefore, we need to solve the given equation when s(t) < 15.
Therefore, -4.9t² + 10t + 16 < 15 will give the time when the ball is lower than 15m off the ground.
Simplifying the inequality we get,
-4.9t² + 10t + 1 < 0.
We know that this is a quadratic equation, therefore, we can solve for t by using the quadratic formula.
The quadratic formula is given by, t = (-b ± sqrt(b² - 4ac))/2a
Where a, b and c are constants of the quadratic equation ax² + bx + c = 0.
Substituting the values, we get, t = (-10 ± sqrt(10² - 4(-4.9)(1)))/2(-4.9)
On solving, we get, t = 0.4082s or t = 1.942s.
Therefore, the ball is lower than 15 meters at approximately 0.41 seconds and 1.94 seconds after it is thrown.
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A charity needs to report its typical donations received. The following is a list of the donations from one week. A histogram is provided to display the data. 10, 10, 10, 10, 15,15,15,19, 20, 20, 20, 25, 25, 25, 30, 30, 55, 55 A graph titled Donations to Charity in Dollars. The x-axis is labeled 10 to 19, 20 to 29, 30 to 39, 40 to 49, and 50 to 59. The y-axis is labeled Frequency. There is a shaded bar up to 8 above 10 to 19, up to 6 above 20 to 29, up to 2 above 30 to 39, and up to 2 above 50 to 59. There is no shaded bar above 40 to 49. Which measure of variability should the charity use to accurately represent the data? Explain your answer.
The charity should use the range as a measure of variability to accurately represent the data. Range is the difference between the largest and smallest values in a dataset. So, the range as a measure of variability is appropriate for this dataset because it gives a sense of how spread out donations are from the smallest to the largest.
In this case, the largest donation was $55 and the smallest was $10, so the range is $55 - $10 = $45. Using the range as a measure of variability is appropriate for this dataset because it gives a sense of how spread out the donations are from the smallest to the largest.
It is also easy to calculate and understand, which makes it useful for reporting to donors and stakeholders.
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Basic Cable Company A charges $30 per month plus a setup fee of $75. Basic Cable Company B charges $40 per month, but due to a special promotion is not currently charging a setup fee. Write an equation for each cable company modeling the total cost y for a subscription lasting x months. When is it more economical for a person to choose Basic Cable Company B over Basic Cable Company A
Answer:
Basic Cable Company A= 30x + 75
Basic Cable Company B= 40x
After 7.5 months, it's more economical to go with Company A. Before 7.5 months, Company B is cheaper
Step-by-step explanation: