Answer: A
Step-by-step explanation: If the melting point of Bromine is 19 degrees and the melting point of mercury is 57 degrees less than that then x (which is mercury's melting point) plus 57 degrees will equal 19.
Find the Gradient of the line drawn below.
Answer:
3 ,0
Step-by-step explanation:
In vector calculus, the gradient of a scalar-valued differentiable function f of several variables is the vector field \nabla f whose value at a point p is the "direction and rate of fastest increase". Wikipedia
Answer:
1/3
Step-by-step explanation:
We need two easy-to-read points on grid intersections.
Look at the point on the y-axis. It is (0, 3).
Now go up to the right until you find the next easy-to-read point.
It is (3, 4) which is on a grid intersection.
gradient = run/rise
rise = distance in y (vertical distance)
run = distance in x (horizontal distance)
We start at (0, 3) and go to (4, 4) by going only vertically and horizontally.
From (0, 3), go 1 unit up. That is a rise of 1.
Then go 3 units right. That is a run of 3.
gradient = rise/run = 1/3
Answer: 1/3
Tanya bought a cake for $18 and cookies for $1.50 each. If she spent $27.00, how many cookies did she buy?
Answer: 18 cookies
Step-by-step explanation:
27 divided by 1.50 = 18
Answer:
Step-by-step explanation:
6 cookies
The freshmen competed with the sophomores to see who could raise the most money by recycling. The appropriate design for testing the significance of the difference between the means is a. related-samples t-test. b. independent-samples t-test. c. one-sample i-test. d. z-test
The appropriate design for testing the significance of the difference between the means is called an independent-samples t-test.
The Independent Samples t- test analyzes the means of two separate groups to observe if there is statistical support that the population mean values are statistically substantially different.
A parametric test is said to be the Independent Samples t Test and the Independent t Test is another name for this test. Both examine the significance of a discrepancy between two means.
Independent-sample t tests compare scores on the same variable for the two different groups of cases, whereas paired-sample t tests compare scores on two different variables for the same group of instances.
When doing a t-test, it is usual to make the following assumptions: like the measuring scale, random sampling, normality of the data distribution, sufficiency of the sample size, and an equality of variance in standard deviation.
The appropriate design for testing the significance of the difference between the means is - b. independent-samples t-test.
To know more about 'independent-samples t-test' related questions
visit- https://brainly.com/question/22691741
#SPJ4
Find an equation for the line that passes through the points (-5,1) and (1,3) .
The equation of the line that passes through the points (-5,1) and (1,3) is x - 3y = -8
Determining the equation of a line that passes through a set of pointsFrom the question, we are to determine the equation of the line that passes through the given points.
The given points are (-5, 1) and (1, 3)
Using the formula,
(y - y₁) / (x - x₁) = (y₂ - y₁) / (x₂ - x₁)
Then,
(y - 1) / (x - (-5)) = (3 - 1) / (1 - (-5))
Simplify
(y - 1) / (x + 5) = 2 / (1 + 5)
(y - 1) / (x + 5) = 2 / 6
(y - 1) / (x + 5) = 1/3
Cross multiply
3(y - 1) = 1(x + 5)
3y - 3 = x + 5
x + 5 = 3y -3
x - 3y = -3 - 5
x - 3y = -8
Hence, the equation is x - 3y = -8
Learn more on Equation of a line here: https://brainly.com/question/21967006
#SPJ1
what is the largest area of a rectangle that can be inscribed in a semicircle of radius 6? round to the nearest whole numb
The largest area of a rectangle that can be inscribed in a semicircle of radius 6 is 36.
What is the semicircle?
A semicircle is a one-dimensional locus of points that makes up one-half of a circle in mathematics. A semicircle's whole arc is always 180 degrees long. It just has one symmetry line.
The equation of the semicircle is
x² + y² = r² .............(1)
The area of the rectangle is
A = 2xy ..................(2)
From equation (1), we get
y² = r² - x²
y = √r² - x²
Plugging this value in equation (2)
A = 2x√r² - x²
Differentiating wrt. x using the product rule,
[tex]\frac{dA}{dx} = 2\sqrt{r^2 - x^2} - 2\frac{x^2}{\sqrt{r^2 - x^2} }[/tex]
[tex]\frac{2r^2 - 4x^2 }{\sqrt{r^2 - x^2} }[/tex]
The critical points are when
[tex]\frac{dA}{dx} = 0[/tex]
that is
[tex]\frac{2r^2 - 4x^2 }{\sqrt{r^2 - x^2} } = 0[/tex]
r² = 2x²
x = r/√2
Then,
y = √r² - x²
= √r² - (r/√2)²
= r/√2
The maximum area is
A = 2 . r/√2 . r/√2 = r²
A = r² = (6)² = 36
Hence, the largest area of a rectangle that can be inscribed in a semicircle of radius 6 is 36.
To learn more about the semicircle visit,
https://brainly.com/question/27155435
#SPJ4
Define T in L(C2) by T(w,z)=(−z,w).
Find the generalized eigenspaces corresponding to the distinct eigenvalues of T.
I believe that once I have the eigenvalues, I know how to find the eigenspaces, but I'm not sure I'm looking for the eigenvalues correctly.
I know that if the eigenvalues are a,b corresponding to (w,0) and (0,z) respectively, then (ab)=1, since a(w)=−z implies ab(−z)=−z. But I think my whole approach to this is wrong and that I'm missing some very elementary idea.
T is the linear transformation described by T(w,z) in L(C2). This indicates that the linear transformation T changes two-dimensional vectors of the type (w,z) to (-z,w).
To get T's eigenvalues, solve the equation T(v) = v, where is the eigenvalue and v is the eigenvector. By solving this equation, we discover that T's eigenvalues are λ1 = -1 and λ2 = 1.
For each eigenvalue, the associated eigenspaces are the subspaces of C2 that are spanned by the eigenvectors of T. The eigenspace is the subspace covered by the eigenvector λ1= -1 is (1,0). The eigenspace is the subspace spanned by the eigenvector λ2= 1 is (0,1).
As a result, the subspaces covered by (1,0) and (1,1) are the generalized eigenspaces corresponding to the different eigenvalues of T. (0,1).
Learn more about eigenvalues here:
https://brainly.com/question/15423383
#SPJ4
There is a group of students were given a spelling test. The table shows their marks. TABLE: Marks: 6,7,8,9,10 Frequency:5,4,7,10,4. What is the mean mark of the group?
The mean mark of the group would be 8.
Used the concept of mean that states,
Mathematicians find the mean by adding up all the numbers in a data collection, then dividing that total by the number of numbers.
Given that,
There is a group of students who were given a spelling test.
The table shows their marks.
By dividing the total number of students by the sum of each mark's frequency and each mark, you can determine the group's mean grade:
[tex]\text { Mean Mark } = [ (6 \times 5) + (7 \times 4) + (8 \times 7) + (9 \times 10) + (10 \times 4) ] \div30[/tex]
[tex]= [ 30 + 28 + 56 + 90 + 40 ] \div 30[/tex]
[tex]= 244 \div 30[/tex]
[tex]= 8.1333333333...[/tex]
[tex]= 8 (\text{ nearest whole number}})[/tex]
Therefore, the value of the mean is 8.
To learn more about the mean visit:
https://brainly.com/question/1136789
#SPJ12
Given h(x) = 4x - 4, solve for x when h(x) = 0.
The value x in the equation h(x) = 4x-4 is, x =1
What is polynomial?Polynomial functions are functions of a single independent variable.
To solve for x
Since h(x) =0
substitute h(x) into equation
h(x) = 4x - 4
0=4x - 4
Add 4 to both sides
4x = 4
Divide both side by 4
4x/4 = 4/4
x = 1
therefore, the value of X= 1
Learn more about polynomial here; https://brainly.com/question/2833285
#SPJ1
Chris had bowling and hockey training on the 1 May. He has bowling training every 8 days and hockey training every 2 days. On what date will he have both training sessions again? answer quick pls
The date that Chris will have both training sessions again is May 9.
How to calculate the date?In mathematics, a multiple simply means the product of any quantity. It should be noted that a multiple illustrate to the product of a number given.
In this situation, since Christ has bowling training every 8 days and hockey training every 2 days. The lowest common multiple for 2 and 8 is 8.
Therefore, the next date will be the addition of the day of the training and the number of days that are needed when the lowest common multiple was calculated. This will be illustrated thus:
= May 1 + 8 days
= May 9
The next training is May 9.
Learn more about multiples on:
brainly.com/question/26856218
#SPJ1
F(x)=3x
3
kx−5, and
x
1
x1 i a factor of
f
(
x
)
f(x), then what i the value of
k
k?
The function will have a value of 0 at x = 1. In that case, the variable "k" will have a value of 2.
What is function?A mathematical phrase, rule, or law that establishes the link between an independent variable and a dependent variable (the dependent variable). In mathematics, functions exist everywhere, and they are crucial for constructing physical links in the sciences. A relation between a collection of inputs and outputs is known as a function. A function is, to put it simply, a connection between inputs in which each input is connected to precisely one output.
Given f(x) = 3x³ + kx – 5, and the factor of the given function is (x – 1).
If the factor (x – 1) is zero. Then the value of the function will be zero.
x – 1 = 0
x = 1
At x = 1, the value of the function will be zero. Then the value of the variable 'k' will be calculated as,
f(1) = 3(1)³ + k(1) – 5
0 = 3 + k – 5
k = 5 – 3
k = 2
The function's value will be 0 at x = 1. The variable "k" will then have a value of 2.
To know more about function,
https://brainly.com/question/25808525
#SPJ4
alent to 5(2x-1)+2(x+4)
Answer:
12x+3
Step-by-step explanation:
distribute the 5 to both the 2x and -1
10x-5
do the same with the the 2. Distribute the 2 to the x and to the 4.
2x+8
10x-5+2x+8
add like terms: the 10x and the 2x are like terms and the -5 and 8 are like terms
12x+3 : the answer
a fisherman in a boat is drinking a cup of hot coffee. the large lake below his boat is full of cold water. which statement is an accurate comparison of the lake water and the coffee?(1 point)
A comparison of hot coffee and cold lake is, the heat from the coffee will be absorbed by the cold lake through convection method of heat transfer.
What is convection ?Heat is transferred through the convection, which is basically large-scale movement of molecules inside gases and the liquids. Conduction is basically used to move heat from one of the object to the fluid initially, but fluid motion is all responsible for the bulk of the heat transfer.
Convection is a process by which heat is always transferred through fluids as a result of the material motion.It occurs as in both gases and the liquids.It could be forced or be natural.Bulk transfers of some of the given fluid are necessary.Conservation of energy
The principle of conservation of the energy states that the total energy of an isolated system is always in conserved state.
Heat lost by all the hot coffee = Heat absorbed by all the cold lake
Heat transfer process
Heat from the coffee will all be absorbed by the cold lake through convection method of the heat transfer.
Thus, the comparison of hot coffee and the cold lake is, the heat from the coffee will all be absorbed by the cold lake through convection method of the heat transfer.
Learn more about heat transfer, visit :
brainly.com/question/12072129
#SPJ4
assume a simple model with only two countries: the united states and germany, and two goods: beer and motorcycles. suppose that the opportunity cost for the united states to produce 1 beer is 3 motorcycles and the opportunity cost for germany to produce 1 beer is 1/2 motorcycles. which of the following statements is true
The statement opportunity cost for Germany to produce 1 beer is 1/2 motorcycles is true.
The German economy would be better off if it produced beer and traded motorcycles with the US.
Germans would benefit from specializing in producing beer and engaging in trade with the United States since their opportunity cost is lower (1/2 is less than 3).
A country is said to be having a comparative advantage in producing a good if it can produce it at a lower opportunity cost. Germany has a lower opportunity cost in producing beer so it has a comparative advantage in making beer.
To Learn more about similar opportunity cost questions:
https://brainly.com/question/15959659
#SPJ4
if it is known that the lifetime of a light bulb has an exponential distribution with parameter 1/250, what is the probability the bulb works
The probabilities for the given hours are,
[tex](a) Pr(100 < x < 250) = 0.302440605\\(b) Pr(\frac{x > 300}{x > 200})=0.670320046\\ (c) Pr(x > 100) = 0.670320046[/tex]
What is probability?
The area of mathematics known as probability deals with numerical descriptions of how likely it is for an event to happen or for a proposition to be true. A number between 0 and 1 is the probability of an event, where, roughly speaking, 0 denotes the event's impossibility and 1 denotes its certainty.
P.D.F , [tex]f(x) = \frac{1}{250}e^\frac{-x}{250} ; x \geq 0\\[/tex]
C.D.F , [tex]F(X) = 1-e^\frac{-x}{250} ;x \geq 0[/tex]
(a)
[tex]Pr(100 < x < 250) = F(250) - F(100)\\Pr(100 < x < 250) = (1-e^\frac{-250}{250})-(1-e^\frac{100}{250} )\\ Pr(100 < x < 250) = (e^\frac{-2}{5}-e^-^1) \\ Pr(100 < x < 250) = 0.670320046 - 0.367079441\\ Pr(100 < x < 250) = 0.302440605[/tex]
(b)
[tex]Pr(\frac{x > 300}{x > 200}) = \frac{Pr[(x > 300) intersection(x > 200)]}{Pr(x > 200)} \\ Pr(\frac{x > 300}{x > 200}) = \frac{Pr(x > 300)}{Pr(x > 200)} \\Pr(\frac{x > 300}{x > 200}) = \frac{1 - F(300)}{1-F(200)} \\Pr(\frac{x > 300}{x > 200}) = \frac{e^\frac{-300}{250} }{e^\frac{-200}{250} } \\Pr(\frac{x > 300}{x > 200}) = e^\frac{-2}{5} \\Pr(\frac{x > 300}{x > 200})= 0.670320046[/tex]
(c)
[tex]Pr(x > 100) = 1-Pr(x < 100) = 1- F(100) = e^\frac{-100}{250} = e^\frac{-2}{5} = 0.670320046[/tex]
Hence, the probabilities for the given hours are,
[tex](a) Pr(100 < x < 250) = 0.302440605\\(b) Pr(\frac{x > 300}{x > 200})=0.670320046\\ (c) Pr(x > 100) = 0.670320046[/tex]
To know more about probability, click on the link
https://brainly.com/question/24756209
#SPJ4
Complete question:
Complete question is attached below,
Alejandro has a computer support business. He estimates that the cost to run his business can be represented by X = 48 x + 500, where x is the number of customers. He also estimates that his income can be represented by R = 65 x - 145. How many customers he will need in order to break even?
The number of customers Alejandro will need in order to break even is 38 customers.
How to find the number of customers to break even?Given data:
Cost of business = 48 x + 500
Income = R = 65 x - 145
Let x is the number of customers.
Income equation
R= 65x- 145
Substitute 48x + 500 for y
48x + 500 = 65x -145
Substract 48x from both side
500 = 17x - 145
Add 145 to each side
645 = 17x
Divide both side by 17x
x =645 /17
x = 37.9
x = 38 customers (Approximately)
Therefore the number of customers is 38 customers.
Learn more about break even here
brainly.com/question/21137380
#SPJ1
What is the simplified version of the expression
(x^1/2 y^1/9 )^3
The simplified version of the expression (x¹/² y¹/⁹)³ is (x³/² y¹/³)
How to determine the simplified expression?From the question, we have the following parameters that can be used in our computation:
(x^1/2 y^1/9 )^3
Rewrite the expression properly
So, we have
(x¹/² y¹/⁹)³
Open the brackets
This gives
(x¹/² y¹/⁹)³ = (x¹/²)³ * (y¹/⁹)³
Evaluate the expression in brackets
(x¹/² y¹/⁹)³ =(x³/² y¹/³)
Hence, the solution is (x³/² y¹/³)
Read more about expressions at
https://brainly.com/question/4344214
#SPJ1
I need HELPPP!!!!! Pls
#2 Which equation is the correct slope intercept form equation for the
table below?
X
Y
3
5
y=2x-11
y= 2x + 11
y= 11x-2
y=-2x +11
6
-1
q
-7
12
- 13
9 points
Where is the hole for the following function located? f (x) = startfraction x + 3 over (x minus 4) (x + 3) endfraction.
A hole can be found at x = -3.
What is unitary method?Area is the total amount of space that an object's shape or a flat (2-D) surface occupy.
Create a square on paper by using a pencil. Two dimensions make it up. A shape's area on paper is the space it takes up.
Imagine that your square is made up of smaller unit squares.
The area of a figure is equal to the number of unit squares required to completely cover the surface area of a particular 2-D shape. Square cms, square feet, square inches, square meters, etc. are a few common units for measuring area.
To get the area of the square figures presented below, draw unit squares with 1-centimeter sides. Therefore, the shape will be measured.
According to our question-
When the denominator is zero, the function will have a hole at the x-values and become undefined. In a language of mathematics:
There are two answers to this equation:
The function will have a gap at those x-values.
Hence, A hole can be found at x = -3.
learn more about unitary method click here:
brainly.com/question/24587372
#SPJ4
a family is traveling due west on a road that passes a famous landmark. at a given time the bearing to the landmark is n 62° w, and after the family travels 9 miles farther the bearing is n 38° w. what is the closest the family will come to the landmark while on the road? (round your answer to two decimal places.) mi
The closest distance the family will come to the landmark while on the road is 12.03 miles.
Here, the situation represented in the question can be depicted as shown in the image below.
The family moves from F1 to F2 as the angle changes from 62 to 38.
Now, using trigonometric ratios in the smaller triangle we have-
Cot 62 = X/Y
X = Y Cot 62
Similarly, Cot 38 = (X + 9)/ Y
Substituting the value of X in the above equation we get-
Y Cot 38 = (Y Cot 62 + 9)
Y Cot 38 - Y Cot 62 = 9
Y(Cot 38 - Cot 62) = 9
Y = 9/ (Cot 38 - Cot 62)
Y = 9/ (1.2799 - 0.5317)
Y = 9/ 0.7482
Y = 12.028
Thus, the closest distance the family will come to the landmark while on the road is 12.03 miles.
Learn more about trigonometry here-
https://brainly.com/question/7331447
#SPJ4
Which 2 recycling plants have equivalent ratios of green bottles recycled in one day?
Recycling| Green bottles recycled|total recyled
A. ..............| .........12.............................| 135
B............... |......... 16............................ | 172
C............... | .........14............................ | 154
D.............. |.......... 18............................ | 198
Plants C and D have the same ratios of green bottles to total bottles recycled.
What is Ratio?The ratio is defined as a relationship between two quantities, it is expressed as one divided by the other.
The table is given in the question,
As per the given question, the required solution would be as:
For plant A,
The ratio of green bottles to total bottles
⇒ 16/172 = 4/43
For plant B,
The ratio of green bottles to total bottles
⇒ 12/135 = 4/45
For plant C,
The ratio of green bottles to total bottles
⇒ 14/154 = 1/11
For plant D,
The ratio of green bottles to total bottles
⇒ 18/198 = 1/11
Thus, plants C and D have the same ratios of green bottles to total bottles recycled.
Learn more about the Ratio here:
brainly.com/question/1504221
#SPJ1
Pls Help me, It's Urgent.
The relationship between RS and RT is RT is the base of this isosceles triangle.
What is congruency?We know two similar planer figures are congruent when we have sides or angles or both that are the same as the corresponding sides or angles or both.
We know the sum of all the interior angles in a triangle is 180°.
Given, A triangle RST,
So, ∠S + ∠T + ∠R = 180°.
50° + 65° + ∠R = 180°.
∠R = 65°.
This is an isosceles triangle with two similar sides RS and ST.
The relation between RS and RT is RT is the base of this isosceles triangle.
learn more about congruency here :
https://brainly.com/question/7888063
#SPJ1
[tex]sin^2x=\frac{secx-cosx}{secx}[/tex]
There are three commonly used trigonometric identities.
Sin x = 1/ cosec x
Cos x = 1/ sec x
Tan x = 1/ cot x or sin x / cos x
Cot x = cos x / sin x
sin²x = (sec x - cos x) / sec x is,
sin²x + cos²x = 1
(proved)
What are trigonometric identities?There are three commonly used trigonometric identities.
Sin x = 1/ cosec x
Cos x = 1/ sec x
Tan x = 1/ cot x or sin x / cos x
Cot x = cos x / sin x
We have,
sin²x = (sec x - cos x) / sec x
We will prove that,
sin²x + cos²x = 1
sec x = 1/cos x
Now,
sec x - cos x
= 1/cos x - cos x
= (1 - cos²x) / cos x
Now,
sin²x = (1 - cos²x) / [(cos x) x 1/cos x]
sin²x = 1 - cos²x
sin²x + cos²x = 1
Proved
Thus,
sin²x = (sec x - cos x) / sec x is,
sin²x + cos²x = 1
Learn more about trigonometric identities here:
https://brainly.com/question/14746686
#SPJ1
how to evaluate 8.1 plus 7.9 when p=6 and r=7
The value of the expression will be;
⇒ 56.5
What is an expression?
Mathematical expression is defined as the collection of the numbers variables and functions by using operations like addition, subtraction, multiplication, and division.
Given that;
The expression is,
⇒ 8.1p + 7.9
And, The values are,
p = 6 and r = 7
Now,
Since, The expression is,
⇒ 8.1p + 7.9
Substitute p = 6, we get;
⇒ 8.1 × 6 + 7.9
⇒ 48.6 + 7.9
⇒ 56.5
Thus, The value of the expression will be;
⇒ 56.5
Learn more about the mathematical expression visit:
brainly.com/question/1859113
#SPJ1
solve the simultaneous equation
5x-4y=19
x+2y=8
determine the value(s) of the local extrema you identified in the previous step. write dne for all extrema that do not exist. separate multiple answers with a comma, if necessary.
Local minimum at: (1, -7) , (3, -7).
Local maximum at : DNE
What to find: Local extrema.
To solve the given problem, we will use the steps below:
Local extrema:
A local extremum of a function is the point at which a maximum or minimum value of the function in some open interval containing the point is obtained.
OR
Local extrema on a function are points on the graph where the -coordinate is larger (or smaller) than all other -coordinates on the graph at points ''close to'' . A function has a local maximum at , if for every near .
Locate the local extremum from the graph.
From the graph given, we have two local minimum.
At x = 1, f(1) =-7
Hence, the local minimum is (1, -7)
At x=3, f(3) =-7
Hence, the local minimum is ( 3, - 7)
Therefore, the local minimum are (1, -7) , (3, -7).
Learn more about Local Minimum:
https://brainly.com/question/10878127
#SPJ4
if θ measures 0 radians, what is the measure of the angle with an initial ray in the 3 o'clock position and a terminal ray passing through the car?
The measure of the angle with an initial ray in the 3 o'clock position and a terminal ray passing through the car is 0 or origin.
Terminal ray:
In geometry, terminal ray refers the ray in the terminal position, after the rotation, is called the terminal side of the angle.
Given,
Here we need to find if θ measures 0 radians, then the measure of the angle with an initial ray in the 3 o'clock position and a terminal ray passing through the car.
While we looking into the given question,
the value of θ = 0 radians
And the Slope of terminal ray is calculated by using the formula,
=> tan θ
Then Slope = tan 0
Now, by using radians calculator,
=> tan 0 = 0
Therefore, the slope of the terminal ray is 0 which means the origin of the line.
To know more about Terminal ray here.
https://brainly.com/question/14058033
#SPJ4
What does -3+x-1/3x+4 equal
[tex]\frac{2x+3}{3}[/tex]
Step-by-step explanation:1. Combine multiplied terms into a single fraction-3 + x - [tex]\frac{1}{3}[/tex]x + 4
-3 + x + [tex]\frac{-x}{3}[/tex] + 4
2. Add the numbers-3 + x + [tex]\frac{-x}{3}[/tex] + 4
1 + x + [tex]\frac{-x}{3}[/tex]
3. Find common denominator1 + x + [tex]\frac{-x}{3}[/tex]
[tex]\frac{3}{3}[/tex] + [tex]\frac{3x}{3}[/tex] + [tex]\frac{-x}{3}[/tex]
4. Combine fractions with common denominator[tex]\frac{3}{3}[/tex] + [tex]\frac{3x}{3}[/tex] +[tex]\frac{-x}{3}[/tex]
[tex]\frac{3 + 3x - x}{3}[/tex]
5. Combine like terms[tex]\frac{3 + 3x - x}{3}[/tex]
[tex]\frac{3 + 2x}{3}[/tex]
6. Rearrange Terms[tex]\frac{3 + 2x}{3}[/tex]
[tex]\frac{2x+3}{3}[/tex]
Solution:[tex]\frac{2x+3}{3}[/tex]
I hope my answer helped you! If you need more information or help, comment down below and I will be sure to respond if I am online. Have a wonderful rest of your day!
two independent samples of sizes 40 and 50 are randomly selected from two populations to test the difference between the population means . the sampling distribution of the sample mean difference is:
The sampling distribution is t= 88 degrees of freedom.
To find the sampling distribution of the sample mean difference we need to do a two-sample t-test: equal variances.
When we do a two-sample t-test, we have to take into account the following assumptions:
1) the sample variances are normal.
2) the sample variances of both populations are equal.
Now, let the sample size be [tex]n_x[/tex] and [tex]n_y[/tex] respectively and the means be [tex]x^-[/tex] and [tex]y^-[/tex] respectively.
Now, we are assuming that the distribution of x and y are
[tex]x\sim N([/tex]mewx, [tex]\sigma x = \sigma[/tex])
[tex]y\sim N[/tex] (mewy, [tex]\sigma y = \sigma[/tex])
Accordingly, the system of hypothesis is defined by:
Null hypothesis: mewx=mewy
alternatively, it can also be mewx≠ mewy
Then, the random sample t is distributed as [tex]t\sim t_n_x+ny-2[/tex] with the degrees of freedom given as df= [tex]n_x+n_y-2[/tex] =40+50-2= 88
So, in this case answer will be 88 degrees of freedom.
To know more about sampling distribution: https://brainly.com/question/14090787
#SPJ4
assume that blood pressure readings are normally distributed with a mean of 116 and a standard deviation of 4.8. if 36 people are randomly selected, find the probability that their mean blood pressure will be less than 118.
The probability that mean blood pressure less than 118 is 0.9938.
We have given that,
blood pressure are normally distributed mean of 116
i.e. μ = 116
standard deviation σ = 4.8
n = 36
and we have to find probability that their mean blood pressure will be less than 118.
The formula to find the above probability is,
P(Z=X) = (x - μ) / (σ/[tex]\sqrt{n}[/tex] )
⇒ P(Z < 118) = (118 - 116) / 4.8/[tex]\sqrt{36}[/tex]
= 2 / (4.8/6)
= 2/0.8
P(Z < 118) = 2.5
From the z-table the value of z at 2.5 is 0.9938,
⇒ P(Z < 118) = 0.9938.
Therefore the probability that their mean blood pressure will be less than 118 is 0.09938.
To know more about probability here
https://brainly.com/question/13143657
#SPJ4