Answer:
k = -5
Step-by-step explanation:
According to the Remainder Theorem, when we divide a polynomial f(x) by (x − c), the remainder is f(c).
Therefore, if we divide polynomial f(x) = x³ + kx + 9 by (x - 2) and the remainder is 7 then:
f(2) = 7To find the value of k, simply substitute x = 2 into the function, equate it to 7 and solve for k.
[tex]\begin{aligned}f(2)=(2)^3 + k(2) + 9 &= 7\\8+2k+9&=7\\2k+17&=7\\2k&=-10\\k&=-5\end{aligned}[/tex]
Therefore, the value of k is -5.
he brain volumes (cm3) of 20 brains have a mean of 1190.7 cm3 and a standard deviation of 120.4 cm3. Use the given standard deviation and the range rule of thumb to identify the limits separating values that are significantly low or significantly high. For such data, would a brain volume of 1411.5 cm3 be significantly high?
Answer:
Step-by-step explanation:
The range rule of thumb states that the range of a dataset is approximately four times the standard deviation. Using this rule, we can estimate the range of brain volumes in this dataset:
Range ≈ 4 × standard deviation = 4 × 120.4 cm3 = 481.6 cm3
To identify the limits separating values that are significantly low or significantly high, we can add and subtract half the range to and from the mean:
Lower limit = mean - (range/2) = 1190.7 cm3 - (481.6 cm3 / 2) = 949.9 cm3
Upper limit = mean + (range/2) = 1190.7 cm3 + (481.6 cm3 / 2) = 1431.5 cm3
Therefore, any brain volume below 949.9 cm3 or above 1431.5 cm3 would be considered significantly low or significantly high, respectively.
A brain volume of 1411.5 cm3 is within the range of values that are not considered significantly high or low. Its z-score can be calculated as follows:
z-score = (1411.5 - 1190.7) / 120.4 = 1.84
Using a standard normal distribution table or calculator, we can find that the probability of getting a z-score of 1.84 or higher is approximately 0.0336. This means that a brain volume of 1411.5 cm3 would be considered uncommon, but not extremely rare.
Christine has a six-sided dice numbered from 1 to 6. She rolled it a total of 50 times. It landed on an odd number 21 times. a) Work out the relative frequency of the dice landing on an odd number. Give your answer as a decimal. b) If the dice were fair, what would the theoretical probablity of it landing on an odd number be? Give your answer as a decimal. c) Is the dice definitely biased or definetely not biased, or is it impossible to tell? Write a sentence to explain your answer.
A) Relative frequency is number of times an event happened over total number of events:
Answer is 21/50 = 0.42
B) On a 6 sides die, there are 3 even numbers and 3 odd numbers, so the theoretical probability of landing on odd would be 3/6 = 0.50
C) Because the die has an equal amount of chance landing on even or odd, both are 3/6, then the dice is not biased.
Debra, Alan, and Shen have a total of 122 in their wallets. Alan has less than $7 Debra. She has 3 times what Alan has. How much do they have in their wallets?
Answer:
Debra has $10.50, Alan has $3.50, and Shen has $108.
Step-by-step explanation:
Set up a system of equations to represent the situation.
Let a represent Alan's money, d represent Debra's money, and s represent Shen's money.
1. a + d + s = 122
2. a = d - 7
3. d = 3a
Use equation's 1 and 2 alone to calculate a and d. Substitute Eq 3 into Eq 2 such that
a = 3a - 7
-2a = -7
a = $3.50
Use Alan's money to calculate Debra's money.
d = 3(3.5)
d = $10.50
Now use values of a and d to calulate Shen's money, given the total.
s + 3.5 + 10.5 = 122
s + 14 = 122
s = $108
So, Debra has $10.50, Alan has $3.50, and Shen has $108.
Determine the equation of the ellipse with foci (2,4) and (2,-8), and co-vertices (10,-2) and (-6,-2).
Answer:
To find the equation of the ellipse, we need to use the standard form of the equation for an ellipse centered at the origin:
((x-h)^2)/a^2 + ((y-k)^2)/b^2 = 1
where (h, k) is the center of the ellipse, a is the distance from the center to the end of the major axis, and b is the distance from the center to the end of the minor axis.
Step 1: Find the center of the ellipse
The center of the ellipse is halfway between the two foci:
center = ((2+2)/2, (4-8)/2) = (2,-2)
Step 2: Find the length of the major axis
The distance between the two foci is 12 units (the absolute value of the difference in the y-coordinates):
c = 12
The length of the minor axis is the distance between the two co-vertices, which is 16 units:
2b = 16
b = 8
To find the length of the major axis, we use the relationship between a, b, and c in an ellipse:
c^2 = a^2 - b^2
a^2 = b^2 + c^2
a^2 = 8^2 + 12^2
a^2 = 256
a = 16
Step 3: Plug in the values to the standard form of the equation
((x-2)^2)/16^2 + ((y+2)^2)/8^2 = 1
Therefore, the equation of the ellipse is:
((x-2)^2)/256 + ((y+2)^2)/64 = 1
What percent of 2160 is 270?
The percent of the number 2160 which is 270 is 12.5%.
Given a number 2160.
It is required to find the percent of this number which is 270.
Let x be the percent of 2160 which is 270.
Then, this can be written as:
2160 × (x/100) = 270
2160 × x = 270 × 100
2160 × x = 27000
x = 27000 / 2160
= 12.5
Hence the required percentage is 12.5%.
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Which of these shapes is a polygon?
Image :
A
B
C
Answer: The correct answer is C, the X.
change these fractions to decimals 1/35
Answer:
Step-by-step explanation:
find the linear approximation of f (x )equals fifth root of x when x equals 32.
This is the linear approximation of f(x) = 5th root of x when x = 32. To find the linear approximation of f(x) = 5th root of x when x = 32, we need to first find the equation of the tangent line at x = 32.
The derivative of f(x) = 5th root of x is: f'(x) = 1/(5x⁴/⁵)
So, at x = 32, we have f(32) = 2 and f'(32) = 1/80.
Using the point-slope form of a line, we can write the equation of the tangent line as:
y - 2 = (1/80)(x - 32)
Simplifying this equation, we get:
y = (1/80)x + (79/40)
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Please help me, can’t figure out which one is actually correct for Jackson
If Jackson feels confident that he can score higher than 69 on the final exam, then he should take it. Otherwise, he would be better off not taking the final exam.
What is probability?
Probability is a branch of mathematics that deals with the study of random events or phenomena. It is the measure of the likelihood or chance of an event or set of events occurring.
If Jackson does not take the final exam, the average of his three highest scores would be:
(72 + 73 + 70)/3 = 71.67.
If Jackson takes the final exam, there are two possibilities:
If Jackson scores lower than any of his previous exam scores, then his lowest score will be dropped, and his grade will be calculated based on his four highest scores, which would be:
(73 + 72 + 70 + X)/4.
where X is his score on the final exam. In this case, taking the final exam would not benefit Jackson, as his grade would be based on his three highest scores (72, 73, and 70) regardless of his performance on the final exam.
If Jackson scores higher than any of his previous exam scores, then his lowest score will be the lowest of his first four exams, and his grade will be calculated based on his four highest scores, which would be:
(73 + 72 + X1 + X2)/4.
Therefore, If Jackson feels confident that he can score higher than 69 on the final exam, then he should take it. Otherwise, he would be better off not taking the final exam.
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Angle 4 and angle ____ are vertical angles.
A: 1
B: 2
C: 3
Answer:
angle 4 and angle 1 are vertical angles
Step-by-step explanation:
vertical angles are opposite each other
3. You get three summer jobs to help you save for college expenses. In your job as a cashier,
you work 20 hours per week and earn $9.50 per hour. Your second and third jobs are at a local
hospital. There, you earn $9.00 per hour as a payroll clerk and $7.00 per hour as an aide. You
always work 10 hours less per week as an aide than you do as a payroll clerk. Your total weekly
salary depends on the number of hours you work at each job.
a. Determine the input and output variables for this situation.
b. Explain how you calculate the total amount earned each week.
c. If x represents the number of hours you work as a payroll clerk, represent the number of
hours you work as an aide in terms of x.
d. Write an equation that describes the total amount you earn each week. Use x to represent
the input variable and y to represent the output variable. Simplify the expression as much
as possible.
e. If you work 12 hours as a payroll clerk, how much will you make in one week?
f. What are the practical replacement values for x? Would 8 hours at your payroll job be a
realistic replacement value? What about 50 hours?
g. When you don't work as an aide, what is your total weekly salary?
Please help!
Hence the output variable (total weekly earnings) is a function of the input variable (number of hours worked as a payroll clerk) and may be expressed by the equation y = 16x + 120.
What is a Variable?A variable is anything that may be altered in the context of a mathematical notion or experiment. Variables are frequently denoted by a single symbol. .
a. Input variables: hours worked as a cashier, payroll clerk, and assistant.
The total amount earned each week is the output variable.
b. To determine the weekly total, multiply the number of hours worked at each job by the hourly rate and put them together. As a result, the equation would be:
Total weekly wage = (hours worked as a cashier x cashier hourly rate) + (hours worked as a payroll clerk x payroll clerk hourly rate) + (hours worked as an aide x rate per hour as an aide)
c. The amount of hours worked as an assistant is always 10 hours fewer than that of a payroll clerk. Therefore, if x denotes the number of hours worked as a payroll clerk, then the number of hours worked as an assistant may be denoted as (x - 10).
d. The equation describing the total money earned each week is as follows:
(20 x 9.5) + (x x 9) + ((x - 10) x 7) = y
This expression is simplified as follows:
y = 190 + 9x - 70 + 7x
y = 16x + 120
Hence the output variable (total weekly earnings) is a function of the input variable (number of hours worked as a payroll clerk) and may be expressed by the equation y = 16x + 120.
f. The realistic replacement values for x would be determined by the maximum number of hours you may work at each job as well as the amount of time available to work. Working 8 hours as a payroll clerk may be a reasonable substitute value if you have restricted availability, but 50 hours is unlikely.
g. If you do not work as an aide, you may calculate your total weekly income by setting the number of hours worked as an aide to zero in the calculation for the total amount earned each week. This results in:
y = 16x + 120 + 0
y = 16x + 120
As a result, the total weekly wage would be determined only by the number of hours performed as a cashier and payroll clerk.
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HELP ASAP! 10 POINTS! PLEASE HELP ME FIND THE AREA AND THE PERIMETER!!!!
The area of the composite shape using the area formula for the different shapes is 460.48ft².
What are composite shapes?The area of composite shapes refers to the space occupied by any composite shape. A composite shape is a shape that is made by connecting a few polygons to form the required shape.
These figures or shapes can be built from a wide range of shapes, such as triangles, squares, quadrilaterals, etc. Divide a composite item into basic forms such a square, triangle, rectangle, or hexagon to get its area.
Now in the question,
First let us find the area of the semi-circle.
Area of semi-circle = πr²/2
= [3.14 × (16/2) ²]/2
= (3.14 × 8²)/2
= 200.96/2
= 100.48ft²
Now coming to the rectangle,
area of the rectangle = l × b
= 20 × 15
= 300ft²
Now for calculating the area of the triangle,
area = 1/2 × b × h
= 1/2 × 12 × 10
= 60ft²
Therefore, the area of the total figure = 100.48 + 300 + 60 = 460.48ft².
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Which graph represents the function f(x)=∣x+1∣−3?
By looking at the vertex of the graph, we can see that the fourth graph is the correct option.
Which graph represents the function f(x)=∣x+1∣−3?Here we want to see which one of the given graphs represents the given absolute value function.
Remember that for the absolute value function:
f(x) = |x - a| + b
Has a vertex at the point (a, b) and opens up.
Then in this particular case, with the function f(x)=∣x+1∣−3, the vertex will be at the point (-1, -3), so we just need to identify which one of the given graphs has that vertex, we can see that the correct option is the fourth option.
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Lincoln spent $95 of his pocket money every month and saved the rest. This month he
decided to spend only $75, thereby increasing his savings by 40%.
a)What was his pocket money every month?
b) Find the ratio of his expenditure to his savings for this month?
in excercises 7 and 8 find bases for the row space and null space of a. verify that every vector in the row(a) is orthogonal to every vector in null(a)
The bases for the row space and null space of A, we put A into reduced row echelon form and solve for the null space. The dot product of basis vectors shows they are orthogonal.
To find the bases for the row space and null space of A, we perform row operations on A until it is in reduced row echelon form:
[ 1 -1 3 | 5 ] [ 1 -1 3 | 5 ]
[ 2 1 -5 | -9 ] -> [ 0 3 -11 | -19]
[-1 -1 2 | 2 ] [ 0 0 0 | 0 ]
[ 1 1 -1 | -1 ] [ 0 0 0 | 0 ]
The reduced row echelon form of A tells us that there are two pivot columns, corresponding to the first and second columns of A. The third and fourth columns are free variables. Therefore, a basis for the row space of A is given by the first two rows of the reduced row echelon form of A:
[ 1 -1 3 | 5 ]
[ 0 3 -11 | -19]
To find a basis for the null space of A, we solve the system Ax = 0. Since the third and fourth columns of A are free variables, we can express the solution in terms of those variables. Setting s = column 3 and t = column 4, we have:
x1 - x2 + 3x3 + 5x4 = 0
2x1 + x2 - 5x3 - 9x4 = 0
-x1 - x2 + 2x3 + 2x4 = 0
x1 + x2 - x3 - x4 = 0
Solving for x1, x2, x3, and x4 in terms of s and t, we get:
x1 = -3s - 5t
x2 = s + 2t
x3 = s
x4 = t
Therefore, a basis for the null space of A is given by the vectors:
[-3 1 1 0]
[ 5 2 0 1]
To verify that every vector in the row space of A is orthogonal to every vector in the null space of A, we compute the dot product of each basis vector for the row space with each basis vector for the null space:
[ 1 -1 3 | 5 ] dot [-3 1 1 0] = 0
[ 1 -1 3 | 5 ] dot [ 5 2 0 1] = 0
[ 0 3 -11 | -19] dot [-3 1 1 0] = 0
[ 0 3 -11 | -19] dot [ 5 2 0 1] = 0
Since all dot products are equal to zero, we have verified that every vector in the row space of A is orthogonal to every vector in the null space of A.
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_____The given question is incomplete, the complete question is given below:
in excercises 7 and 8 find bases for the row space and null space of a. verify that every vector in the row(a) is orthogonal to every vector in null(a). a = [ 1 -1 3 5 2 1 0 1 -2 -1 -1 1]
The table below shows the number of painted pebbles of Claire and Laura. If Greg chooses a pebble at random from the box 75 times, replacing the pebble each time, how many times should he expect to choose a yellow pebble?
A) 11
B) 33
C) 32
D) 22
Answer:
B) 33 times.
Step-by-step explanation:
The total amount of pebbles is 50. There is 22 yellow pebbles.
Note that 3/2 * 50 is 75. 3/2 * 22 = 33.
He should expect to choose a yellow pebble B) 33 times.
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Perpendicular lines form acute angles.
A) True
B) False
Answer:
B) False
Step-by-step explanation:
Perpendicular lines form right angles. It does not form acute angles.
can you help me to solve this question?
The slope of tangent line is, m= [tex]-\frac{1}{14}[/tex]
Equation of tangent line, for m= [tex]-\frac{1}{14}[/tex] and b= [tex]\frac{53}{7}[/tex] is, 14y = -x + 106
Define the term slope of line?The slope of a line is a measure of how steeply it rises or falls as it moves horizontally. It is calculated by dividing the change in the vertical coordinate by the change in the horizontal coordinate between two points on the line.
Slope of tangent, m = [tex]\frac{dy}{dx}[/tex]
f(x) = y = [tex]\sqrt{57-x}[/tex]
y = [tex](57-x)^{\frac{1}{2}}[/tex]
Differentiate the above equation y with respect to x.
[tex]\frac{dy}{dx} = \frac{1}{2} * (57-x)^{1-\frac{1}{2} }* (-1)[/tex]
[tex]\frac{dy}{dx} = -\frac{1}{2} * (57-x)^{-\frac{1}{2} }[/tex]
[tex]\frac{dy}{dx} = -\frac{1}{2\sqrt{57-x} }[/tex]
Therefore, the slope (m) of tangent line f(x) at point (8, 7) is,
[tex]\frac{dy}{dx} | _{(8, 7)} = -\frac{1}{2\sqrt{57-8} } = - \frac{1}{14}[/tex]
Equation of tangent line f(x) at point (8, 7) is,
y = mx + b
7 = [tex]-\frac{1}{14}[/tex] × 8 + b
b = [tex]\frac{53}{7}[/tex]
So, Equation is, y = [tex]-\frac{1}{14}x + \frac{53}{7}[/tex]
Therefore, 14y = -x + 106
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Is this figure a polygon dont answer if you don’t know the answer
Polygon - a plane figure with at least three straight sides and angles, and typically five or more.
Answer:
No
Step-by-step explanation:
Since a polygon has straight sides, with 3 or more, it cannot be a polygon since one side is curved.
A mark on the side of a pier shows the
water is 4 feet deep. At high tide, the
water level rises 21 feet. About how deep
is the water at high tide?
Assume that the readings at freezing on a batch of thermometers are normally distributed with a mean of 0°C and a standard deviation of 1.00°C. A single thermometer is randomly selected and tested. Find the probability of obtaining a reading between -0.08°C and 1.68°C.
The probability of obtaining a reading between -0.08°C and 1.68°C is approximately 0.4854 or 48.54%.
What are the four types of probability?Probability is the branch of mathematics concerned with the occurrence of a random event, and there are four types of probability: classical, empirical, subjective, and axiomatic.
The readings at freezing on a set of thermometers are normally distributed, with a mean () of 0°C and a standard deviation () of 1.00°C. We want to know how likely it is that we will get a reading between -0.08°C and 1.68°C.
To solve this problem, we must use the z-score formula to standardise the values:
z = (x - μ) / σ
where x is the value for which we want to calculate the probability, is the mean, and is the standard deviation.
The lower bound is -0.08°C:
z1 = (-0.08 - 0) / 1.00 = -0.08
1.68°C is the upper bound:
z2 = (1.68 - 0) / 1.00 = 1.68
We can now use a standard normal distribution table or calculator to calculate the probabilities for each z-score.
The probability of obtaining a z-score of -0.08 or less is 0.4681, and the probability of obtaining a z-score of 1.68 or less is 0.9535, according to the table. We subtract the probability associated with the lower bound from the probability associated with the upper bound to find the probability of obtaining a reading between -0.08°C and 1.68°C:
P(-0.08°C x 1.68°C) = P(z1 z z2) = P(z 1.68) minus P(z -0.08) = 0.9535 - 0.4681 = 0.4854
As a result, the chance of getting a reading between -0.08°C and 1.68°C is approximately 0.4854 or 48.54%.
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Given the equation x² + 4x + y²-2y = 20: (HINT: Type in the equation is the desmos calculator and get the answers from the graph.)
What is the radius of the circle?
What is the center of the circle?
Answer:
The radius of the circle is 3.
The center of the circle is (-2, 1).
Step-by-step explanation:
Rewrite the equation in standard form:
We need to rewrite the given equation in standard form (x - h)² + (y - k)² = r², where (h, k) is the center of the circle and r is the radius. To do this, we complete the square for both the x and y terms.
x² + 4x + y²-2y = 20
(x² + 4x + 4) + (y² - 2y + 1) = 20 + 4 + 1
(x + 2)² + (y - 1)² = 25
Identify the center and radius:
Now that we have the equation in standard form, we can identify the center and radius of the circle.
The center is the point (-2, 1), which we can read directly from the equation.
The radius is the square root of the number on the right side of the equation, which is 5. Therefore, the radius is sqrt(5) or approximately 2.236.
Alternatively, we can also use the Desmos graphing calculator to plot the equation and visually determine the center and radius. When we plot the equation, we see that it forms a circle with center (-2, 1) and radius 3.
which of the following assumptions must be true in order for this to be the correct sampling distribution
Since means cannot be smaller than 0, the sampling distribution of the mean is always right skewed.
No matter the sample size, the form of the sampling distribution of means is always the same as the population distribution.
We require two assumptions in order to apply the sampling distribution model to sample proportions: The selected values must be independent of one another, according to the independence assumption. The Sample Size Assumption demands that the sample size, n, be sufficiently large.
While doing a t-test, it is typical to make the following assumptions: the measuring scale, random sampling, normality of the data distribution, sufficiency of the sample size, and equality of variance in standard deviation.
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the actual question is :
Which of the following is true about the sampling distribution of the mean?
a. It is an observed distribution of scores
b. It is a hypothetical distribution
c. It will tend to be normally distributed with a
standard deviation equal to the population
standard deviation
d. The mean will be estimated by the standard
error
e. Both (a) and (b)
Find the volume of a frustum of a right circular cone with height 30, lower base radius 21 and top radius 11. Volume =?????
Please Show your steps!!!!!!!
The volume of the frustum of right circular cone = 7730 cube
The volume of the frustum of the right circular cone:
The formula for the Volume of Frustum of Cone (V)=[tex]\frac{1}{3} \pi H (R^2+r^2+Rr )[/tex]
where,
H = Height of frustum
R = Radius of lower base
r = Radius of top base
According to given question,
Height of frustum(H) = 30 units
Radius of lower base(R) = 21 units
Radius of top base (r) = 11 units
Substituting all the given values in the formula of volume of the frustum of the cone we will get,
The volume of a frustum of a right circular cone(V) =[tex]\frac{1}{3} \pi H (R^2+r^2+Rr )[/tex]
[tex]=\frac{1}{3}*30(21^2+11^2+21*11)\\\\=10*(441+121+211)\\=10*(773)\\=7730 unit^3[/tex]
The volume of the frustum of the right circular cone = 271.22
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Two containers designed to hold water are side by side, both in the shape of a cylinder. Container A has a diameter of 12 feet and a height of 9 feet. Container B has a diameter of 8 feet and a height of 20 feet. Container A is full of water and the water is pumped into Container B until Container B is completely full.
After the pumping is complete, what is the volume of the empty space inside Container A, to the nearest tenth of a cubic foot?
Step-by-step explanation:
the volume of container B is Travers from A to B.
so, the volume of the empty space in A is exactly the volume of container B.
the volume of a cylinder is
base area × height = pi×r² × height.
the reside is as always half of the diameter.
r = 8/2 = 4 ft
the volume of the empty space in A = the volume of container B =
= pi×4² × 20 = pi×16 × 20 = 320pi = 1,005.309649... ≈
≈ 1,005.3 ft³
Figure ABCD has been reflected across the y-axis to form figure
WXYZ. Which of the following statements is true?
A. MLA =MLY
B. MLD = MLX
C. AB = WX
D. AB = YZ
Lucy is trying to find the radius of a circle. She is stuck on this step: 121=r
2
What is the radius?
Answer:
I am not good at this but i gess itis 11 √121 equals 11
Executive Bonuses A random sample of bonuses (in millions of dollars) paid by large companies to their executives is shown. Find the mean and modal class for the data. Class boundaries Frequency 0.5-3.5 3.5-6.5 6.5-9.5 9.5-12.5 12.5-15.5 11 12 4 2 1
The mean bonus paid by large companies to their executives is $5 million and the modal class is 3.5-6.5.
How to calculate the mean and the modal class for the dataTo find the mean, we need to find the midpoint of each class and multiply it by the frequency, then add up all of these values and divide by the total frequency:
Class boundaries Midpoint Frequency Midpoint x Frequency
0.5-3.5 2 11 22
3.5-6.5 5 12 60
6.5-9.5 8 4 32
9.5-12.5 11 2 22
12.5-15.5 14 1 14
Total 150
Mean = (Midpoint x Frequency) / Total Frequency
Mean = 150 / 30
Mean = 5
Therefore, the mean bonus paid by large companies to their executives is $5 million.
To find the modal class, we need to look for the class with the highest frequency. In this case, the class with the highest frequency is 3.5-6.5, with a frequency of 12. Therefore, the modal class is 3.5-6.5.
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An 8 foot long ladder is leaning against a wall. The top of the ladder is sliding down the wall at the rate of 2 feet per second. How fast is the bottom of the ladder moving along the ground at the point in time when the bottom of the ladder is 4 feet from the wall.
"The rate at which the bottom of the ladder moving along the ground at the point in time when the bottom of the ladder is 4 feet from the wall is calculated to be 3.464 ft/s."
At a pace of 2 feet per second, the lower end of the ladder is being pulled away from the wall.
At a specific moment, when the lower end of the ladder is 4 feet from the wall, we should determine the rate at which the bottom of the ladder is lowering.
From the point t, the bottom of the ladder is x m, the top of the ladder is y m from the wall.
x² + y² = 64
Differentiating the given relationship with regard to t,
2x dx/dt + 2y dy/dt = 0
x dx/dt + y dy/dt = 0
We need to find out dx/dt at x = 4.
dy/dt = -2
At x = 4, we have,
x² + y² = 64
16 + y² = 64
y² = 48
y = 4√3
Put in the known values to find out dx/dt,
x dx/dt + y dy/dt = 0
4 dx/dt + 4√3 (-2) = 0
4 dx/dt = 8√3
dx/dt = 2√3 = 3.464
Thus, the bottom of the ladder is calculated to be moving at the rate 3.464 ft/s.
The figure can be drawn as shown in the attachment.
To know more about speed:
https://brainly.com/question/13548149
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Would appreciate any help
Answer:
Step-by-step explanation:
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