Answer:48?
Step-by-step explanation:
I as of now am not completely sure of this is the correct answer.
Which expression would be easier to simplify if you used the associative property to change the grouping?
The expression that would be easier to simplify if you used the associative property to change the grouping is D. (160 + 40) + 27.
What is the associative property?The associative property of some binary operations in mathematics means that rearranging the parentheses in an expression will not change the result. Associativity is a valid rule of replacement for expressions in logical proofs in propositional logic.
This law simply states that when adding and multiplying numbers, you can change the grouping of the numbers in the problem and the answer will not change.
Addition and multiplication are both affected by the associative property. The reason for this is that you are combining numbers to get a total in both of these operations. You are combining values with addition. It makes no difference how you group these to put them together. The associative property of addition states that the addends can be grouped in various ways without changing the outcome.
In this case, (160 + 40) + 27 can simply be (40 + 160) + 27.
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What is the value of x in the equation 3x-4y=65, when y=4?
Answer: The answer is 27
Answer:
27
Step-by-step explanation:
I hope its helpful to you.
Emma has a rain gauge on her deck to measure the amount of rain that falls in the area. After a storm with steady rain, there were 4.23 inches of water in the rain gauge. If the storm lasted 3 hours, how much water did the rain gauge collect every hour?
Answer:
1.41 inches per hour
Step-by-step explanation:
volume of water for 3 hrs=4.23 inches
v of water for 1 hours=4.23/3=1.21inches
Let R be an equivalence relation on a set A. Prove the following statement directly from the definitions of equivalence relation and equivalence class. For every a and b in A, if [a] = [b] then a Rb. Some of the sentences in the following scrambled list can be used to prove the statement. By definition of equivalence class, a E[b]. Let b E[a]. Then by definition of equivalence class, b Ra. Since R is symmetric, if b R a then a R b. | Thus, a Ra, and so, by definition of equivalence class, a E [a]. Since [a] = [b] and a E [a], then a E [b] by definition of set equality. | Hence, by definition of equivalence class, a Rb. By definition of equivalence relation, R is reflexive. Proof: Construct a proof by selecting appropriate sentences from the list and putting them in the correct order. 1. Suppose R is an equivalence relation on a set A, a and b are in A, and [a] = [b]. 2. ---Select--- 3. ----Select--- 4. ---Select--- 5. ---Select---
If the R is an equivalence relation then for every a and b in set R , if a = b then aRb exists.
If R is an equivalence relation on set A, a and b are in A and [a]=[b]
By the definition of the equivalence relation we can say that R is reflexive
Hence aRa and so by definition of equivalence class a ∈ [a] .
Since [a] = [b] and a ∈ [a] we can say that a ∈ [b] by the definition of set equality.
Now we will use the definition of equivalent class we can say that aRb .
An equivalence relation is a reflexive, symmetric, transitive binary link. The relationship of equipollence between line segments in geometry is one example of an equivalence relation.
Each equivalence relation separates the underlying set into distinct equivalence classes. Two items in the given set are only comparable to one another if and when they belong to the same equivalence class.
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Based on recent demand for single family homes in a growing city, it is recommended potential home buyers put 20 percent down when making an offer. A mortgage loan officer would like to test the claim that the average percent down on a single family home purchase is greater than the recommended 20 percent. To test this claim, at the 5% significance level, the mortgage loan officer collects the following data on a sample of 22 recent home purchases and records the percent down. The following is the data from this study: Sample size =22 recent home purchases Sample mean =24 percent down Sample standard deviation =9 percent down Identify the null and alternative hypothesis for this study by filling in the blanks with the correct symbol (=,≠,<, or > to represent the correct hypothesis.)
This enabled the borrower to obtain 90 percent financing while avoiding the additional cost of pmi. these loans are more commonly referred to as piggyback mortgage loans.
A loan is the lending of cash via one or more individuals, organizations, or different entities to other individuals, corporations, etc. The recipient incurs a debt and is normally susceptible to pay hobby on that debt till it is repaid as well as to repay the foremost amount borrowed.
A mortgage is a shape of debt incurred by using an character or different entity. The lender—commonly a business enterprise, economic organization, or authorities—advances a amount of money to the borrower. In return, the borrower agrees to a sure set of phrases together with any finance charges, hobby, repayment date, and different situations.
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Polygon P is dilated from the origin by a scale factor other than 1 to create polygon P′.
Determine whether each statement is true or false. Select True or False for each statement.
A. Polygon P is similar to polygo
n P′. TrueFalse
B. Polygon P is congruent to polygon P′. TrueFalse
C. The side lengths of polygon P are equal to the corresponding side lengths of polygon P′. TrueFalse
D. The angle measurements of polygon P are equal to the corresponding angle measurements of polygon P′. TrueFalse
The correct options are: Polygon P is similar to polygon P′ and The angle measurements of polygon P are equal to the corresponding angle measurements of polygon P′
What is dilation of figure?The dilation of a figure is enlargement or reduction of its original image to final image by a certain scale factor.
Given that, Polygon P is dilated from the origin by a scale factor other than 1 to create polygon P′
We know that, in dilation, both figures are similar not congruent, because they get enhanced or reduced by a certain scale factor, if scale factor is 1 then they can be congruent also.
Since, both figure are similar, therefore, their corresponding angles are congruent.
Hence, correct options are ; Polygon P is similar to polygon P′ and The angle measurements of polygon P are equal to the corresponding angle measurements of polygon P′.
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PLEASE HELPPPPPPPPP QUICKKKK
WILL MARK BRAINLEST
please look in down below all in there
a test has a mean of 85 with a standard deviation of 5. which of the following scores is within one standard deviation of the mean?
A test's standard deviation is 5 and its mean is 85. scores is within one standard deviation of the mean is 25/n^12.
The square root of the variance of a random variable, sample, mean ,statistical population, data set, or probability distribution is that variable's standard deviation. Although less robust in practice, it is algebraically simpler than the average absolute deviation.The fact that the standard deviation is expressed in the same unit as the data, as opposed to the variance, is a useful characteristic of the statistic.
variance = 5^2 = 25
standard deviation of the mean = ( variance / n )^1/2
= (25/n)^1/2
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If f is continous on [a,b], then f attains an absolute maximum value f(c) and absolute minimum value f(d) at some numbers c and d in [a,b].
True
False
If f is continous on [a,b], then f attains an absolute maximum value f(c) and absolute minimum value f(d) at some numbers c and d in [a,b] then it is a true statement
What is an absolute maximum?
An absolute maximum point is a point where the function obtains its greatest possible value. Similarly, an absolute minimum point is a point where the function obtains its least possible value.
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Two components of a minicomputer have the following joint pdf for their useful lifetimes X and Y. (If an answer doesn't exist enter DNE.) f(x, y) = xe−x(1 + y) x ≥ 0 and y ≥ 0 0 otherwise Determine E(XY).
The value of E(XY) is equivalent or equal to -1 according to the joint pdf having function f(x, y) = xe^−x(1 + y) x ≥ 0 and y ≥ 0 0.
Given that:
f(x,y) = xe^-x(1+y), where x ≥ 0 and y ≥ 0 0.
E(XY) = ∫∞ ∫∞ xy. xe^−x(1 + y) dx dy
0 0
E(XY) = ∫∞ ∫∞ x^2y . e^−x(1 + y) dx dy
0 0
E(XY) = ∫∞ x^2 . e^−x (∫∞ y e^-xy dy) dx
0 0
E(XY) = ∫∞ x^2 . e^−x (-1/x) dx
0
E(XY) = - ∫∞ x . e^−x dx
0
E(XY) = - 1
Two components of a minicomputer have the following joint pdf for their useful lifetimes X and Y are equal to i.e. E(XY) = -1.
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Help me on these please!. Thank you whoever. 13 points!!
Answer:
1. $105
2. $144
Step-by-step explanation:
For the first question:
4.20 × 25 = 105
For the second question:
4.80 × 30 = 144
Could you please give me brainliest for this? Thank you!
To weigh your cat, you hold it while you step on the scale. By yourself, you weigh 130. 6 130. 6 pounds. Holding your cat, you weigh 142. 5 142. 5 pounds. How much does your cat weigh?.
Answer: 11.9 pounds
Step-by-step explanation:
142.5 - 130.6 = 11.9
A function f (x) is graphed on the coordinate plane. What is the function rule in slope-intercept form? Afunction f (>) is graphed on the coordinate plane What is the function rule in slope-intercept fom? Enter your answer in the box f(r) Basic x2
The required function of the line would be y = 2x + 1.
Function rule in slope-intercept form:The slope-intercept form is one rule to represent linear function rules.
f(x) = mx+b is sometimes used. In any scenario, m and b describe the line's overall features. The slope is denoted by m, while the y-intercept is denoted by b.
Linear equations, or straight-line equations, can be quickly recognized as they have no terms with exponents in them. For example, you will find an x or a y , but never an x². Each linear equation describes a straight line, which can be expressed using the slope intercept form equation.
According to the given question,
The coordinates of the y-intercept would be (0, 1).
The value of the x-coordinate is 1 when y-coordinate is 3.
Here the line passes through points (0, 1) and (1, 3).
Let the required linear function would be
y - y₁ = (y₂ - y₁)/(x₂ -x₁ )[x₂ -x]
x₁ = 0, y₁ = 1
x₂ = 1, y₂ = 3
⇒ y - y₂ = (y₂ - y₁)/(x₂ -x₁ )[x -x₂]
⇒ y - 3 = (3 - 1)/(1 - 0 )[x -1]
⇒ y - 3 = (2)[x -1]
⇒ y - 3 = 2x - 2
⇒ y = 2x - 2 + 3
⇒ y = 2x + 1
Therefore, the required function of the line would be y = 2x + 1 which is shown in the given question.
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Which graph best represents the function f(x) = (x + 1)(x − 1)(x − 4)? (4 points) Graph of a cubic polynomial that falls to the left and rises to the right with x intercepts negative 3, 2, and 3. The graph intersects the y axis at a point between 10 and 15. Graph of a cubic polynomial that falls to the left and rises to the right with x intercepts negative 3, 2, and 3. The graph intersects the y axis at a point between 15 and 20. Graph of a cubic polynomial that falls to the left and rises to the right with x intercepts negative 3, 1, and 3. The graph intersects the y axis at a point between 5 and 10. Graph of a cubic polynomial that falls to the left and rises to the right with x intercepts negative 1, 1, and 4. The graph intersects the y axis at a point between 0 and 5.
A graph which best represents the polynomial function f(x) = (x + 1)(x − 1)(x − 4) is: D. Graph of a cubic polynomial that falls to the left and rises to the right with x intercepts negative 1, 1, and 4. The graph intersects the y axis at a point between 0 and 5.
What is a polynomial function?In Mathematics, a polynomial function can be defined as a mathematical expression which comprises intermediates (variables), constants, and whole number exponents with different numerical value, that are typically combined by using mathematical operations.
This ultimately implies that, a polynomial graph touches the x-axis at zeros, roots, solutions, x-intercepts, and factors with even multiplicities.
In this context, we can reasonably and logically deduce that the zeros of a polynomial function are all of the values (x-intercepts) on the x-coordinate that makes this polynomial function equal to zero and these include the following on a graph:
Zeros = (-1, 0)
Zeros = (1, 0)
Zeros = (4, 0)
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if you draw square abcd and extend the sides by equal lengths to form square efgh, what must be the measure of angle heb so that the area of abcd is half the area of efgh?
The measure of angle < HEB = 60 degrees.
Given:
if you draw square abcd and extend the sides by equal lengths to form square efgh.
so that the area of abcd is half the area of efgh.
Let AB = x and HA = x
so area of square ABCD = x * x
= x^2
< HEB = 60 so < BHE = 30
EB = y
HE = 2y
HB = x + y
so x + y = [tex]\sqrt{3}[/tex] y
x = [tex]\sqrt{3}[/tex] y - y
x = ([tex]\sqrt{3}[/tex] - 1 ) y
y = x / ([tex]\sqrt{3}[/tex] - 1 )
squaring on both sides
y^2 = x^2 / ([tex]\sqrt{3}[/tex] - 1 )^2
= x^2 / 3 - 1
= x^2 / 2
Area of EFGH = (2y)^2 = 4y^2 = 2x^2 = 2 * area of ABCD.
Therefore < HEB = 60 degrees.
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In a test of the equality of the percent defectives from two populations when the sample sizes are large (> 30), which of the following approximation methods is appropriate?
Poisson approximation
Hypergeometric approximation
Fisher's approximation
Normal approximation
Chi-square approximation
The number of defectives follows binomial distribution with parameters (n,p) and if n>30 then binomial distribution goes to the Normal' approximation.
Given that,
We have to find which of the following approximation approaches is adequate in a test of the equality of the percent defectives from two populations when the sample sizes are big (> 30).
We know that,
What is a normal approximation?The normal curve is roughly followed by the sample distribution of averages or proportions from numerous independent experiments. The population value that corresponds to a sample proportion or average is its expectation.
Therefore, the number of defectives follows binomial distribution with parameters (n,p) and if n>30 then binomial distribution goes to the Normal' approximation.
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logic operators are operators that compare two numbers and produce a true or false result. for example, a > b contains such an operator that compares the numbers in variables a and b if the value in a is greater than the value in b, then this operator returns a true result. otherwise, the operator returns a false result.
The operator used in the statement a > b is a comparison operator. In this case, true will be returned if the value of a is greater than the value of b, whereas false if the value of a is less than the value of b.
What are Comparison Operators?Code decisions require comparison operators. Comparison operators are used in the statement a > b. Using a and b as variables, it compares their values, returning true if a is greater than b, and false otherwise.
By comparing the values of two variables, the program can make decisions. Coders should understand how comparison operators work since they are used frequently in programming.
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=-7x+y=-19
-2x+3y=-9
The system of equation - 7x + y = 19 and - 2x + 3y = - 9 have solution at
(-101/9, -3318/19).
What is linear system of equations?If a system of equations only contains two linear equations with two variables, the system's equation can be graphed, the graph will have two straight lines, and the intersection point(s) of those lines will be the system's solution.
There are only three matching forms of solution for a given system of equations because there are only three different ways that two straight lines in the plane can graph.
Given, A system of equations - 7x + y = 19 and - 2x + 3y = - 9.
Now, multiplying eqn(i) by 2 and eqn(ii) by 7 we get,
- 14x + 2y = 38...(iii) and - 14x + 21y = - 63...(iv)
Now, subtracting eqn(iii) from eqn(iv) we get,
(- 14x + 21y = - 63)
- (- 14x + 2y = 38)
_______________
19y = - 101.
y = - 101/19
and putting the value of y in eqn(iv) we get x = - 3318/19.
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The values for random variables in a Monte Carlo simulation are
a. selected manually.
b. generated randomly from probability distributions.
c. taken from forecasting analysis.
d. derived secondarily using formulas.
The correct option is (B) generated randomly from probability distributions.
The values for random variables in a Monte Carlo simulation are generated randomly from probability distributions.
A frequency distribution that has been idealized is a probability distribution. An individual sample or dataset is described by its frequency distribution. It's the number of times in the dataset that each possible value of a variable appears. The probability of occurrence of a value determines how frequently it appears in a sample.
A random variable can have any number of alternative values and likelihoods within a particular range, and a probability distribution is a statistical function that captures all of these possibilities. This range will be constrained by the minimum and maximum possible values, but the location of the possible value on the probability distribution will rely on a number of other variables.
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please help me!!!
Which number is greatest?
Answer:
It would be the third option, because the square root of 85 is 9.22, and 28/3 is 9.33 repeated.
Hope this helps, have a great day! :D
Step-by-step explanation:
a bin contains 4 items: 1 a, 1 b, 2 c and 6 d. a person randomly selects 3. how many different types of items will be selected
The 4 different types of items will be selected.
What is the combination?
Combinations are mathematical operations that count the number of possible configurations for a set of items where the order of the selection is irrelevant. In combinations, you can select the items in any order.
[tex]nCr = \frac{n!}{(n - r)! \ r!}[/tex]
This formula to find the number of combinations by using r objects from the n objects is also referred as the ncr formula.
so, we have 4 items and a person randomly selects 3.
[tex]nCr = (n, r) = (4, 3)[/tex]
[tex]= \frac{4!}{3!(4 - 3)!}[/tex]
= 4! / 3!
= 4
Hence, The 4 different types of items will be selected.
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Preceding the attack at the Somme on July 1, 1916, the British bombarded the German trenches for eight days. Some 1,537 British guns fired 1,723,873 rounds without letting up. In round figures, what was the average number of rounds fired each day? _________ What was the average number of rounds fired by each gun during the eight days? ___ _
The average number of rounds fired each day is 140.
The average number of rounds fired by each gun during the eight days is 1122.
What is a mean?A mean simply means the average of the set of numbers. It is calculated by adding the numbers and then dividing.
In this situation, the British bombarded the German trenches for eight days and some 1,537 British guns fired 1,723,873 rounds without letting up. The average will be:
= 1,723,873 / 1,537
= 1122 rounds .
The average per day will be
= Average / Number of days
= 1122 / 8
= 140 per day.
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johnny is designing a rectangular poster to contain 12 in2 of printing with a 1-in margin at the top and bottom and a 3-in margin at each side. what overall dimensions will minimize the amount of paper used?
the dimensions will minimize the amount of paper used is with length 4 inch and a width 12 inch.
What is the area of the rectangle?
The area of a rectangle (A) is the product of its length 'a' and width or breadth 'b'. So, Area of Rectangle = (a × b) square units.
We have given
Johnny is designing a rectangular poster to contain 12 in² of printing with a 1-in margin at the top and bottom and a 3-in margin at each side.
Let,
l be the length and w be the width.
Area is A = l * w
Johnny is designing a rectangular poster to contain 12 in² of printing
i.e. Area of the inner printed section 12 = lw .........(1)
A 1-in margin at the top and bottom and a 3-in margin at each side.
i.e. l'=l+2 and w'=w+6
The total Area of the Poster is
A = (l+2) + (w+6) ...........(2)
Substitute the value of l from (1) in (2),
A = (12/w + 2) (w + 6)
A = 12 + 72/w + 2w + 12
A = 24 + 72/w + 2w
Differentiate w.r.t w,
A' = -72/w² + 2
For critical value put A'=0,
-72/w² + 2 = 0
2 = 72/w²
w² = 72/2
w² = 36
w = 6
Differentiate again w.r.t w,
A''(w) = 2(72/w²)
A''(6) = 2(72/(6)²)
A''(6) = 2(72/36)
A''(w) = 2*2 = 4>0
It is minimum at w=6.
Substitute in (1),
12 = lw
l = 2
The dimensions required are
l' = l + 2
= 2+2
= 4 inch
w'=w + 6
= 6 + 6
= 12 inch
Hence, the dimensions will minimize the amount of paper used is with a length 4 inch and a width 12 inch.
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at what rate per annum should p2400 be invested so that it will earn an interest of p800 in 8 years?
The interest rate is 4.17%, according to the question.
What do you mean by interest rate?
An amount that a borrower must pay to a lender as interest during the course of a loan, stated as a percentage of the loan amount is called interest rate.
According to data in the given question,
We have the given values:
Amount to be invested/Principal: 2,400
Amount of Interest: 800
Time: 8 years
Now, we will calculate the rate,
Solve for the rate:
Interest = Principal × Rate × Time
Derive the equation for rate:
Rate = [Interest ÷ (Principal × Time)] × 100
Substitute the given values:
Rate = [800 ÷ (2,400 × 8)] × 100
Rate = [800 ÷ 19,200] × 100
Rate = 0.04167 × 100
Rate = 4.17 %
Therefore, the rate is 4.17%.
Check:
800 = 2,400 × 8 × 0.04167
800 = 800.064
800 = 800
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Akira is redecorating her bedroom. She misread the markings on her ruler and thought a picture frame she bought was 5.2 centimeters wide. The frame's actual width was 4.8 centimeters. What is the percent error for her measurement?
The percentage error is 8.3%
What is percentage?A percentage is a portion of a whole expressed as a number between 0 and 100 rather than as a fraction.
Given that, Akira is redecorating her bedroom. She misread the markings on her ruler and thought a picture frame she bought was 5.2 centimetres wide. The frame's actual width was 4.8 centimetres.
Percentage Error = ((Estimated Number – Actual Number)/ Actual number) x 100.
= (5.2-4.8)/4.8x100 = 8.3%
Hence, The percentage error is 8.3%
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1. If AABC is an equilateral triangle, solve for both x and y.
B
A...
3x + 1
18y-41
49 m
Solving for Sides with OOGEE
A
C
Ind
2. If ARST is an equilateral triangle, find x and the measure of each side
its the second oneee
An anchor 15 3/5 m below the surface of the ocean is lowered 4 1/5 m Then it is pulled up 12 3/5 m what is the anchors new position
The new position of the anchor is 7 1/5 below the surface of the ocean
How to find the new position of the anchorInitially the anchor is located 15 3/5 m below the surface of the ocean, this is same as = -15 3/5 m
The anchor is further lowered and the position now is
= -15 3/5 m - 4 1/5 m
= -99 /5 m
Then the anchor is pulled up 12 3/5 m the new position now is
= -99 /5 m + 12 3/5 m
= -36/5
= -7 1/5
= -7.2
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Please help :') ty ty ty ty ty
Please show your work too! :)
Answer:
I don’t know
Step-by-step explanation:
choose the statement that is false.group of answer choicesa 95% confidence interval is wider than a 90% confidence intervalwhen sampling for means and thinking about the central limit theorem, the n should always be >30.when estimating the standard deviation in calculating confidence intervals, make sure you use the t tables.reducing the variation of a process will increase the width of a given confidence interval relative to that process.
Reducing the variation of a process will increase the width of a given confidence interval relative to that process.
Option C is correct .
What is a confidence interval?
In statistics, the probability that a population parameter will fall between a set of values for a predetermined percentage of the time is referred to as a confidence interval. By employing the dimensions of values used in the computation of the intervals, it is simple to establish the link between components of two confidence intervals. The width is a fundamental component in these range estimates, which are affected by sample size, etc.
Hence, reducing the variation of a process will increase the width of a given confidence interval relative to that process is false.
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when the null hypothesis is not rejected, it is possible a type i error has occurred. possible a type ii error has occurred. possible either a type i or a type ii error has occurred. not possible a type ii error has occurred.
When a null hypothesis is not rejected, a type ii error has occurred.
What is a null hypothesis?A null hypothesis being a statistical hypothesis, states that no statistical significance can be present in a set of observations. Usually, hypothesis testing is a method used to judge the veracity of a given sample.
Sometimes, it is called just null, or even it has a symbol, viz, [tex]H_0[/tex].
We consider generally 4 cases:
[tex]H_0[/tex] is accepted when [tex]H_0[/tex] is true ⇒ A correct decision[tex]H_0[/tex] is rejected but is true⇒ Type i error has occurred and is rejected by us, null hypothesis is present[tex]H_0[/tex] is false but is accepted by us⇒ Type ii error has occurred, null hypothesis is not present. [tex]H_0[/tex] is false and is rejected⇒ A correct decision.According to the given question, we have not rejected the null hypothesis.
Thus, we have two options present, either the type ii error has occurred and null hypothesis is not present, or the null hypothesis is present.
Concluding, when a null hypothesis is accepted, it is possible that a type ii error has occurred.
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