If the diameter of a small red beachball is 8 inches, then the cone with the same radius and a height of a 8 inches would fit into the beachball 1/2 times and the volume of the cone would be about 536 in^3.
What is cone and its formula?They develop as a result of lava pieces being blown into the air by ferocious eruptions, solidifying, and then falling as cinders surrounding the volcanic vent. These cinders, which are typically the size of pebbles, are packed with numerous small bubbles that the lava captured as it solidified. The height of a cinder cone can range from tens to hundreds of metres.A cone has no edges and just one face, which is its round base. A cone only has one vertex or apex point. The cone has a volume of 13 r2h. The cone's total surface area is equal to r(l + r). The cone's slant height is (r2+h2).A cone has a vertex that is not on the base and a single circular base.Explanation :
If the diameter of a small red beachball is 8 inches, then the cone with the same radius and a height of a 8 inches would fit into the beachball 1/2 times, because Centre radius will reduced to point when it reaches its full height.
The volume of the cone would be about 536 in^3.
Volume of a cone = 1/3 π [tex]r^{2}[/tex] *h
= 1/3 x π x [tex]8^{2}[/tex] x 8 = 536
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Answer:
two134Step-by-step explanation:
You want to know how many times the volume of a cone 8 inches in diameter and 8 inches high will fit into the volume of a beachball that is 8 inches in diameter, and you want the approximate volume of the cone.
Sphere volumeThe equation for the volume of a sphere based on its diameter is ...
V = π/6d³
Cone volumeThe equation for the volume of a cone is usually written ...
V = 1/3πr²h
For the cone in this problem, with both diameter and height equal to that of the sphere, we can rewrite the volume equation as ...
V = 1/3π(d/2)²·d = π/12d³ . . . . . . where d=8 inches, the sphere diameter
Volume ratioThen the ratio of the sphere's volume to that of the cone is ...
Vs/Vc = ((π/6)d³)/((π/12)d³) = 12/6 = 2
The volume of the cone will fit into the volume of the sphere two (2) times.
Numerical volume valueThe volume of the cone is ...
V = (π/12)8³ = 128π/3 ≈ 134 . . . . cubic inches
The cone's volume is about 134 in³.
__
Additional comment
Note that we have taken the wording "with the same radius" to mean that the radius of the cone is the same as the radius of the sphere.
Alternatively, it could mean the radius of the cone is the same as the dimension given for the diameter of the sphere. In that case, the volume of the cone is 4 times as great, so its volume of 536 in^3 will fit into the sphere 1/2 times.
Find the missing number/s so that the equation has One solution.
Select all that apply.
__x + 3 = –4x + 17
a
2
b
5
c
7
d
-4
Answer: Choice A, Choice B, Choice C
In other words, it's nearly everything but choice D.
====================================================
Explanation:
Let's say we select "2" as the thing to fill the blank.
2x+3 = -4x+17
2x+4x = 17-3
6x = 14
x = 14/6
x = 7/3
We get one solution in this case.
The same applies for the values 5 and 7. I'll let you do those steps.
In contrast, if we filled the blank with -4, then,
-4x+3 = -4x+17
-4x+4x = 17-3
0x = 14
0 = 14
We get a contradiction which leads to "no solutions".
Visually, the equations y = -4x+3 and y = -4x+17 are parallel lines that never intersect. We need them to intersect if we want a solution. Recall that parallel lines have equal slopes but different y-intercepts. Both sides have a slope of -4 in this case.
Therefore, the quick rule of thumb is this: if the slopes are not equal, then the linear equation has exactly one solution.
What is the value of In e4
Answer:
Pie heysgeusuwhueywgyssyywyw
a) Work out the minimum number of dogs that could have a mass of more than 24 kg
b) Work out the maximum number of dogs that could have a mass of more than 24 kg}.
Mass(kg) Frequency
0≤x<10 2
10≤x<20 7
20≤x<30 12
30≤x<40 6
a) A minimum number of dogs that could have a mass of more than 24 kg is 6.
b) The maximum number of dogs that could have a mass of more than 18 kg is 20.
How to find the minimum and maximum value mean?We will rearrange the function using fundamental algebraic concepts to process the value of x when the derivative equals 0. This response gives us the x-coordinate of the function's vertex, which is the point that the maximum or minimum will occur. To find the minimum or maximum, we will start by rewriting the solution into the original function.
From the given parameters, we can see that the minimum of the values present in the interval 20 to 40 is 6
From the given parameters, we can see that the maximum of the values present in the interval 20 to 40 is;
(12 + 6) = 18
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Question 4
May use your own graph paper for this question. Show all algebraic work for full By graphing, find the coordinates of the vertices of the original triangle H L K, give midsegment triangle MNP are M(-1,3), N(4,0), P(-2,-2).
With the mid segment of the triangle MNP as M (-1, 3), N (4, 0), P (-2, -2) the coordinates of the triangle are
(-7, 1), (5, 5), and (3, -5)How to find the coordinates of the triangle when the mid segment is knownThe coordinates is calculated from the midsegment using the formula
X= (x₂ + x₁)/2
Y = (y₂ + y₁)/2
Vertex 1 and 2: point M (-1, 3),
X
-1 = (x₂ + x₁)/2
-2 = x₂ + x₁
Y
3 = (y₂ + y₁)/2
6 = y₂ + y₁
Vertex 2 and 3: point N (4, 0)
X
4 = (x₂ + x₃)/2
8 = x₂ + x₃
Y
0 = (y₂ + y₃)/2
0 = y₂ + y₃
Vertex 1 and 3: point P(-2, -2)
X
-2 = (x₃ + x₁)/2
-4 = x₃ + x₁
Y
-2 = (y₃ + y₁)/2
-4 = y₃ + y₁
The equations
X
-2 = x₂ + x₁
8 = x₂ + x₃
-4 = x₃ + x₁
Y
6 = y₂ + y₁
0 = y₂ + y₃
-4 = y₃ + y₁
from -2 = x₂ + x₁, we find x₁ = -2 - x₂
plugging in x₁ = -2 - x₂ to -4 = x₃ + x₁ gives
-4 = x₃ + -2 - x₂
-2 = x₃ - x₂
then we have
8 = x₂ + x₃
-2 = x₃ - x₂
solving simultaneously
x₃ = 3, x₂ = 5 then x₁ = -2 - x₂ = -7
from 0 = y₂ + y₃, we find that y₂ = -y₃
plugging in y₂ = -y₃ into 6 = y₂ + y₁ gives
6 = -y₃ + y₁
then we have
-4 = y₃ + y₁
6 = -y₃ + y₁
solving simultaneously gives
y₁ = 1, y₃ = -5, then y₂ = -y₃ = -(-4) = 5
The vertex of the triangle are
(-7, 1), (5, 5), and (3, -5)
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a. When the relationship for a regression is positive, an X score above the mean will correspond to a Y score (above/below) the mean.b. When the relationship for a regression is negative, an X score above the mean will correspond to a Y score (above/below) the mean.
(a) For positive Linear Regression , Y score will be above mean .
(b) For negative Linear Regression , Y score will be below the mean .
What is Linear Regression ?
The term Linear regression analysis is used to predict the value of one variable based on the value of another variable.
Part(a)
when the relationship of regression between two variables is positive then if one variable increase the other variable also increases ,
So , if the the x score is above the mean then the Y score will be also above the mean .
Part(b)
when the relationship of regression between two variables is negative then if one variable increase the other variable decreases ,
So , if the the x score is above the mean then the Y score will be below the mean .
Therefore , (a) Y score will be above the mean .
(b) the Y score will be below the mean .
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determine the sample size needed to construct a 95 % confidence interval to estimate the population proportion is 0.54, and the margin of error is 0.06. use two decimal places for the critical value and round to the nearest integer for your final answer. eg. 48.47
The sample size needed is at least 311.17.
We have that to find our α level, that is the subtraction of 1 by the confidence interval divided by 2. So:
α = [tex]\frac{1-0.95}{2} = 0.025[/tex]
Now, we have to find z in the Z-table as such z has a p-value of 1-α
So it is z with a p-value of , so
1-0.025 = 0.975, so z = 1.96
Now, find the margin of error M as such
[tex]M = z*\frac{sd}{\sqrt{n} }[/tex]
where sd = σ = standard deviation
At least n, in which N is found when M= 0.06 and σ = 0.54. So
[tex]M = z*\frac{sd}{\sqrt{n} } \\0.06 = 1.96 * \frac{0.54}{\sqrt{n}} \\\sqrt{n} = \frac{1.96*0.54}{0.06} \\\sqrt{n} = 17.64\\n = 311.1696\\[/tex]
Rounding off to the nearest integer, we get n = 311.17.
Thus, the sample size needed is at least 311.17.
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Marta's family plans to sell their kitchen table and buy a new one. Marta originally wrote down the length of their old table as 1,602.5 centimeters. She realized she made a mistake and that the table has an actual length of 162.5 centimeters.
Which of the statements correctly compares the digits in the original measurement and the actual measurement?
A. The value of the digit 5 in the original measurement is 10 times the value of the digit 5 in the actual measurement.
B. Removing the digit 0 in the original measurement did not change the value of any digits in the actual measurement.
C. The value of the digit 1 in the actual measurement is 110 the value of the digit 1 in the original measurement.
D. The digit 6 has the same value in both the original measurement and the actual measurement.
The correct option is the value of the digit 1 in the actual measurement is 110 the value of the digit 1 in the original measurement. (option C)
What are the value of the digits in the measurement?Here is the place value of each of the digits in the wrong table length :
1 = thousand
6 = hundred
0 = tens
2 = units
5 = tenth
Here is the place value of each of the digits in the actual table length :
1 = hundred
6 = tens
2 = units
5 = tenth
5 has the same value in both the wrong length and the right length.
The value of 6 in the actual measurement is ten times that of the wrong measurement .
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Marta found a website that sells her favorite style of coffee mugs. She writes the function C(m)=4.50 m+7, where C(m) represents the total cost of ordering m mugs, to decide how many mugs to order. Determine whether each statement about the features of the function is true or false in terms of the context.
The range is {y l y ≥ 11.5\}.
The domain is all real numbers.
The y-intercept is 4.5.
There is no x-intercept.
The rate of change is $ 4.5 per mug.
The true or false values of the statements are:
The range is {y l y ≥ 11.5\}: FalseThe domain is all real numbers: FalseThe y-intercept is 4.5: TrueThere is no x-intercept.: TrueThe rate of change is $4.5 per mug: TrueHow to determine the true statements from the scenario?From the question, we have the following parameters that can be used in our computation:
C(m) = 4.50m + 7
The smallest number of mugs she can sell is 0
So, we have the following equation
C(0) = 4.50 * 0 + 7
Evaluate
C(0) = 0
This means that the range is y ≥ 0
Next, the domain cannot be all real numbers
This is because real numbers include negative and decimal numbers
For the y-intercept, we have
C(m) = 4.50m + 7
Set m to 0
y-intercept = 4.5 * 0 + 7
Evaluate
y-intercept = 7
For the y-intercept, we have
C(m) = 4.50m + 7
Set C(m) to 0
4.5 * x-intercept + 7 = 0
Evaluate
x-intercept = -7/4.5 -- this cannot be taken as the x-intercept because it is a negative number
Also, we have the slope to be 4.5
So, the rate of change is $4.5 per mug
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Determine whether y varies directly with x If so, find the constant of variation and write the function rule.
Does y vary directly with x?
No
Yes
What is the constant of variation? Select the correct choice and fill in any answer boxes in your choice below.
A. k=__ (Simplify your answer. Type an integer or a fraction.)
B. There is no constant of variation.
What is the function rule? Select the correct choice and fill in any answer boxes in your choice below.
A. y=_____
(Simplify your answer. Use integers or fractions for any numbers in the expression.)
B. There is no function rule.
The value of y varies directly with x, and the constant of variation is 3, and function rule y = 3x.
What is Direct Variation?When one value is dependent on another i.e if one value increases with respect to another or if one value decreases with respect to another then we can say that the two quantities are in direct variation.
In simple words, It is the relationship between two variables where one of the variables is a constant multiple of the other.
When two values a and b are varies directly then the relation between them can be shown as given below
=> a ∝ b
=> a = kb here 'k' constant of variation
Here we have
x values 57 63 66
y values 19 21 22
Let's assume that y varies directly with x
=> y ∝ x
=> y = kx ---- (1)
Where k is the proportionality constant
From (1)
We can write k = x/y
From the above calculations, if y varies directly with x then x/y must be a constant.
Now check whether the given value can give a constant
At x = 57 and y = 19
[tex]= > \frac{x}{y} = \frac{57}{19} = 3[/tex]
At x = 63 and y = 21
[tex]= > \frac{x}{y} = \frac{63}{21} = 3[/tex]
At x = 66 and y = 22
[tex]= > \frac{x}{y} = \frac{66}{22} = 3[/tex]
From the above calculation,
For given x and y values, x/y is always constant
Therefore,
It is true that y varies directly with x, and the constant of variation is 3
Here the function rule will be y = x × constant of variation
=> y = 3x
Therefore,
The value of y varies directly with x, and the constant of variation is 3, and function rule y = 3x
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;oowgsvdsgg bss tr tbs
is that even a question bro?
20. You buy 4 online games for $0.99 each. You make 2 in-game purchases for
$3.99 each. What is the total you spent on games?
Answer: $11.94
Step-by-step explanation: 4 x 0.99 = $3.96 and then 2 x $3.99 = $7.98 now $7.98 + $3.96 = $11.94
8. What value of g makes the equation true? g + 4.3 = 7.2 A) 3.5 B) 2.9 C) 11.5 D) 10.1
State whether each linear relationship is also a proportional correct box. Explain why or why not. If it does, writ form y=p x
Proportional relationship?
YES___
No___
Why?
y = p x is Proportional relationship.
What is proportional relationship?
Proportional relationships are relationships between two variables where their ratios are equivalent. Another way to think about them is that, in a proportional relationship, one variable is always a constant value times the other. That constant is know as the "constant of proportionality".
The answer depends on the equation given.
If the equation is in the form y=px, where p is a constant, then it is a proportional relationship. If the equation is in the form y=mx+b, where m and b are constants, then it is not a proportional relationship.To know more about proportional relationship check the given link
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Billing charges for Microsoft 365 Commercial licensing. When a customer purchases a subscription and changes the amount during the subscription period, a full refund is credited then prorated for what was used. For example, if a customer purchased 2 subscriptions for the month of June at $15 each, the total charge for the month would be $30. If they decide to return one subscription 5 days later, the full $30 would be credited then a prorated charge for what was used would be applied. Credit $30 Charge $15 Charge $0.5 * 5 = $2.50 $15 / 30 = $0.5 p/day Total Charge $17.50 Total Credit $12.50 If a customer purchases 10 Microsoft 365 Business Premium licenses at $22 each per month, for a full year then 6 months later decides they only need 5 licenses for the remainder of the year, what would be the total charge and credit for the year?
The customer who purchases 10 Microsoft 365 Business Premium licenses at $22 each per month, for a full year, then 6 months later decides they only need 5 licenses for the remainder of the year, would pay a total charge of $1,980 with a credit of $660 for the year.
How are the total charge and credit computed?The total charge the customer will pay is based on the difference between the total charge for the year and the prorated charge of credit for non-usage.
The charge per month for Microsoft 365 = $22
The charge per month for 10 Microsoft 365 = $220 ($22 x 10)
The charge for 1 year for one Microsoft 365 = $264 (22 x 12)
The charge for 6 months for 10 Microsoft 365 = $1,320 ($220 x 6)
The charge for 12 months for 10 Microsoft 365 = $2,640 (220 x 12)
The prorated charge for 6 months for 5 Microsoft 365 returned = $660 ($2,640 x 5/10 x 6/12)
The initial total charge for the year = $2,640
The total credit for the year = $660
The total charge for the year = $1,980 ($2,640 - $660)
Thus, the customer will pay $1,980 after receiving a prorated credit for 5 returned licenses worth $660.
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What is the slope of 0,0 and 1/3, 7/3
To find the slope of a line that passes through two points, you can use the formula:
slope = (y2 - y1)/(x2 - x1)
In this case, the two points are (0,0) and (1/3, 7/3). Substituting these values into the formula, we get:
slope = (7/3 - 0)/(1/3 - 0)
slope = 7/3
Therefore, the slope of the line that passes through (0,0) and (1/3, 7/3) is 7/3.
0.2x + 2 = 0.2(4 - x)what is the solution of the equation?
show your work!!
Answer:
x = -3
Step-by-step explanation:
0.2x + 2 = 0.2(4 - x)
0.2x + 2 = 0.8 - 0.2x
0.4x = -1.2
x = -1.2/0.4
x = -3
Need quick
Foci: (-2, 0) and (2, 0)
Length of major axis: 8
Find equation of ellipse
The equation of the ellipse is x²/8² + y²/(2√15)² = 1.
What is an equation?An equation is a mathematical statement that is made up of two expressions connected by an equal sign.
Example:
2x + 4 = 9 is an equation.
We have,
Foci: (-2, 0) and (2, 0)
Length of major axis: 8
The equation of an ellipse.
x²/a² + y²/b² = 1
Where a is the major axis and b is the minor axis.
Now,
b² + c² = a²
c = 2
a = 8
b² = a² - c²
b² = 64 - 4
b² = 60
b = √60
b = √(4 x 15)
b = 2√15
Now,
x²/a² + y²/b² = 1
x²/8² + y²/(2√15)² = 1
Thus,
The ellipse equation is x²/8² + y²/(2√15)² = 1.
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Explain the steps in solving 2.14x - 12.18 = -5.76, and write the solution to the equation.
WRITER
Someone please help me with this!!!
Answer:
x = 3
Step-by-step explanation:
You want to solve for x, so you want to get x on one side of the equation. To do this, you can add the -12.18 to both sides of the equation (you add since it's negative).
2.14x - 12.18 = -5.76
2.14x = 6.42
Then you want to get x by itself, without the 2.14 in front of it. To do this, you can divide both sides of the equation by 2.14.
This will give you,
x = 3
Problem Situation: Ike has $126 in his bank account. He gets $20 for his birthday.
He also has a part-time job that pays $8 per hour. How many hours will he need to
work to have $250 in his bank account?
.
Answer: 13h
Step-by-step explanation:
126 + 20 = 146
250 - 146 = 104
104 : 8 = 13
He will need 13h
Answer:
13.5
126 plus 20 is $146
250 minus 146 is 108
108 divided by 8 is 13.5
PLEASE HELP answer 6 and 7 best explanation gets brainliest
Answer:
Imma write it in the explanation
Step-by-step explanation:
6. interior angles, alternate angles
for c to be parallel with d, we need 2 and 7 to be interior angles (a+b=180°, u/c shaped), and 3 and 5 to be alternate angles (a=b, z shaped).
7. 1+3=180°, 2+4=180°
there were 2 parallel lines in a trapezium, so for the c shape on 1 and 3 they add up to 180°, and same thing to 2 and 4.
5. Which of the following is true about the solution to the
system of equations?
3x - 2y = 10
2y = 3x - 16
4
A. The x-value of the solution is4/3
B. The y-value of the solution is -1.5.
C. There are infinitely many solutions to this system.
D. There is no solution to this system.
6
i
Answer:
D
Step-by-step explanation:
3x - 2y = 10 → (1)
2y = 3x - 16 → (2)
substitute 2y = 3x - 16 into (1)
3x - (3x - 16) = 10
3x - 3x + 16 = 10
16 = 10 ← not possible
this indicates the system has no solution.
There is no solution to this system. Therefore, option D is the correct answer.
What is a linear system of equations?A system of linear equations consists of two or more equations made up of two or more variables such that all equations in the system are considered simultaneously. The solution to a system of linear equations in two variables is any ordered pair that satisfies each equation independently.
The given that the system of linear equations are
3x - 2y = 10 -------(i)
2y = 3x - 16
3x-2y=16 -------(ii)
Subtract equation (ii) from equation (i), we get
3x-2y-(3x-2y)=10-16
0≠4
Therefore, option D is the correct answer.
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Consider the expression 40+24 . Find the greatest common factor of the two numbers, and rewrite the expression using the distributive property.
The greatest common factor of 40 and 24 would be; 8.
What is an expression?Expression in maths is defined as the collection of numbers variables and functions by using signs like addition, subtraction, multiplication, and division.
We can rewrite this expression for distribution using the amount of times 8 goes into both numbers as;
8(5 + 3)
Using the distributive property, we get:
8(5) + 8(3) = 40 + 24.
Threfore,
The greatest common factor of 40 and 24 would be; 8.
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i need helpp.....................
Write this ratio as a fraction in simplest form without any units 27 feet to 8 yards
The ratio of 27 feet to 8 yards is 9/8 while converting feet to yards and the ratio is also 9/8 while converting yards to feet.
What are yards and feet?Yards and feet are units use to measure the length of geometrical shapes.
1 foot equal to 0.333 yards and similarly 1 yard equal to 3 feet. There is proportional relationship between them.
what did you get from the above fraction value?We got the same fraction value from the ratio of two units which implies that the two units are proportional.
1 foot =0.333 yard so
27 feet = 9 yards
similarly, 1 yard = 3 feet
so, 8 yard = 24 feet
hence, the ratio is 9/8
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Music Company A charges a $ 15 membership fee and $ 0.75 each to download a song. Music Company B charges $ 0.90 each to
download a song with no membership fee.
a. For what number of songs will both companies charge the same amount? Justify your answer using mathematics.
____songs
You anticipate that you will download 150 songs. Which company should you choose if you want to spend the least amount of
money? Justify your answer using mathematics.
(i) At a total of 100 Songs the Charges for Company A and Company B will be Equal.
(ii) I would rather suggest to select Company A as the Total Charges to download 150 Songs is $127.5
What is Linear Equation in One Variable?
A linear equation is a one-variable equation of a straight line. The variable's only power is 1. Linear equations in one variable have the form ax + b = 0 and are solved using simple algebraic techniques.
Solution:
Let, Songs Downloaded be x
Total Charges of Company A = 15 + 0.75*x
Total Charges of Company B = 0.9*x
(i) Total Charges by Company A = Total Charges by Company B
15 + 0.75*x = 0.9*x
15 = 0.15*x
x = 100 songs
(ii) Charges by Company A to Download 150 Songs = 15 + 0.75 * 150
= 15 + 112.5 = $127.5
Charges by Company B to Download 150 Somgs = 0.9 * 150 = $135
I would rather suggest to select Company A as the Total Charges to download 150 Songs is $127.5
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URGENT!! ILL GIVE BRAINLIEST!!!! AND 100 POINTS!!!
What is the variable in this expression?
4b + 2b + 1⁄4
Answer:
b
Step-by-step explanation:
a variable is an unknown number normally represented by a letter and in this case the variable is b
hopes this helps please mark brainliest
which of the following statements is correct? one-way anova is the same as correlation, but different from two-way anova dependent t-test is the same as one-way anova, but different from independent t-testone-way anova is the same as one sample z-test, but different from paired samples t-test paired samples t-test is the same as dependent t-test, but different from one sample z-test
Option D is the correct answer. Paired samples t-test is the same as the dependent t-test, but different from one sample z-test.
The dependent t-test also called the paired t-test or paired-samples t-test compares which means the two related groups to determine whether there is a statistically significant difference between these means.
The T-test is defined as a univariate hypothesis test that is based on a t-statistic, On the other side, Z-test is also a univariate test that is based on a standard normal distribution.
There is a small comparison between the t-test and z-test:
T-test refers to a type of parametric test that is applied to identify, how the means of two sets of data differ from one another when variance is not given. Z-test implies a hypothesis test that ascertains if the means of two datasets are different from each other when variance is given.The T-test is Based on Student-t distribution whereas z-Test depends on Normal distributionThe Population variance of the t-test is Unknown and for the z-test, it is known, and the Sample Size is Small for the t-test for the z-test size is Large.To know more about T-test and Z-test:
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A university has 25,000 students, of whom 10,000 are older than 25. The registrar draws a simple random sample of 400 students. a) Find the expected value and SE for the number of students in the sample who are older than 25. b) Find the expected value and SE for the percentage of students in the sample who are older than 25. c) The percentage of students in the sample who are older than 25 will be around _____, give or take _____ or so.
The expected value is 160 and SE for the number of students in the sample is 9.78
a)Given: students of which 25000 of which 10000 are older than 25 and 25000-10000=15000 are not older than 25.
we represent 400 students by drawing 400 tickets from a box that contains 15000 tickets labeled 0 and 10000 tickets labeled 1
Expected value and standard deviation of a box:
First, we determine the expected value of the box, which is the sum of all values on the tickets by the number of tickets.
[tex]expected value box=\frac{15000*0+10000*1}{25000}\\\\ =\frac{10000}{25000} =\frac{2}{5}[/tex]
expected value box=0.4
let us next determine the standard deviation using the shortcut formula:
SD=(big number-small number)*√fraction with small number*fraction with a small number.
[tex]SD=(1-0)*\sqrt{\frac{10000}{25000} *\frac{15000}{25000} \\\\SD=1*\sqrt{\frac{2}{5} *\frac{3}{5} } \\SD=1*\sqrt{\frac{6}{25} } =\frac{\sqrt{6} }{5}[/tex]
SD=0.4899.
Expected value sum=Number of draws*expected value box
=400*0.4
Expected value sum=160
standard error of the sum is the product of the square root of the number of draws and the standard deviation of the box.
SE Sum=√number of draws*SD box
SE Sum=√400*0.4899
=20*0.4899
SE Sum=9.78
b)EXpected value and standard error:
The expected value of the percentage is the expected value of the sum divided by the number of draws.
Expected value percentage=Expected value sum/Number of draws*100%
160/400*100
=0.4*100%
Expected value percentage=400%
The standard error of the percentage is the standard error for the sum divided by the sample size:
SE%=SE for number/Number of draws*100%
=9.798/400*100%
=0.0245*100%
SE% =2.45%
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One requirement can be met while the other fails. Show this by finding
(a) A set of vectors in R2 for which x+y stays in the set but 1/2x may be outside.
(b) A set of vectors in R2 (other than two quarter-planes) for which every cx stays in the set but x+y may be outside.
Forever c x stays in the set but x+y may be out side the set.
What is set?
A set comprises elements or members that can be mathematical objects of any sort, including numbers, symbols, points in space, lines, other geometric forms, variables, or even other sets. A set is the mathematical model for a collection of various things.
a consider the set of vectors in [tex]$\mathbb{R}^2$[/tex]
[tex]A=\left\{\left(x_1, x_2\right) \in \mathbb{R}^2 \mid x_2 \geqslant 2\right\} .$$[/tex]
where[tex]$x=\left(x_1, x_2\right)$[/tex]
Then for any [tex]$x=\left(x_1, x_2\right), y=\left(y_1, y_2\right) \in A$[/tex]
ere that[tex]$x+y=\left(x_1+y_1, x_2+y_2\right) \in A\left(\right.$ Since $x_2+y_2 \geqslant 2+2$[/tex]
But take [tex](4,2) \in A$.[/tex]
Then [tex]\frac{1}{2}(4,2)=(2,1) \notin A$.[/tex]
ce. [tex]$\frac{1}{2}(4,2)$[/tex] belongs outside the set
i.. I some vectors in A such that[tex]\frac{1}{2} x \notin A$[/tex].
b Consider the set of vectors in [tex]$\mathbb{R}^2$[/tex]
[tex]A=\left\{\left(x_1, x_2\right) \in \mathbb{R}^2 \mid \begin{array}{ll}\frac{1}{2} x_1 \leq x_2 \leq \frac{3}{2} x_1 & \text { if } x_1 \geqslant 0 \\\frac{3}{2} x_1 \leq x_2 \leq \frac{1}{2} x_1 & \text { if } x_1 < 0\end{array}\right\}$$[/tex]
The geometrical representation of this set is
see that for any scalar [tex]$c, \quad c x=e\left(x_1, x_2\right) \in A$[/tex]. But if we take [tex](3,2) *(-2,3-3) \in A$ but $(3,2)+(-2,-3)=(1,-1) \& A$[/tex].
Thus forever c x stays in the set but x+y may be out side the set.
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