Answer:
Option A
Step-by-step explanation:
If the quadrilateral ABCD is dilated by a scale factor 'k' to form quadrilateral A'B'C'D',
Scale factor = [tex]\frac{\text{Length of one side of the Image}}{\text{Length of one side of the original}}[/tex]
k = [tex]\frac{BA'}{BA}[/tex]
Distance between B(2, -5) and A(-1, -1) = [tex]\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]
= [tex]\sqrt{(2+1)^2+(-5+1)^2}[/tex]
= 5 units
Distance between B(2, -5) and A'(-5.5, 5) = [tex]\sqrt{(-5.5-2)^2+(5+5)^2}[/tex]
= [tex]\sqrt{(-7.5)^2+(10)^2}[/tex]
= 12.5 units
Scale factor 'k' = [tex]\frac{12.5}{5}[/tex]
k = [tex]\frac{5}{2}[/tex]
Therefore, ABCD is dilated by a scale factor [tex]\frac{5}{2}[/tex] about point B.
BA and it's image BA' are on the same line and passes through center of dilation B.
Similarly, lines CD and C'D' will be parallel because they do not pass through center of dilation.
Therefore, Option (A) will be the correct option.
A margin of error tells us how often the confidence interval estimates the parameter incorrectly. how often a confidence interval is correct. how accurate the statistic is when using it to estimate the parameter.
Answer:
how accurate the statistic is when using it to estimate the parameter.
Step-by-step explanation:
The margin of error may be referred to as a range or interval around a calculated statistic. The margin of error usually employed when calculating the confidence interval, will give a certain range of value within the sample statistic. This is sample statistic and margin is used to estimate the parameter albeit a certain percentage or proportion within the sample statistic. This provides the accuracy level at which the statistic will estimate the parameter.
Margin of Error :
Margin of Error = Zcritical * σ/√n ; OR
Margin of Error = Tcritical * s/√n
Where ;
σ = population standard deviation
s = sample standard deviation
Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the z-score of a man 71.2 inches tall. (to 2 decimal places)
Answer:
0.7857
Step-by-step explanation:
Given :
Mean = 69 inches
Standard deviation, = 2.8 inches
The Zscore of a man who is 71.2 inches
The ZSCORE is obtained using the relation :
Zscore = (Score, x - mean) / standard deviation
Zscore = (71.2 - 69) / 2.8
Zscore = 2.2 / 2.8
Zscore = 0.7857
Find the measure of of RA.
Answer:
RA = 24
Step-by-step explanation:
Since the triangle is isosceles ( 2 equal sides ) , then LU is a perpendicular bisector , so
AU = RU , that is
4r = 18 - 2r ( add 2r to both sides )
6r = 18 ( divide both sides by 6 )
r = 3
Then
RA = 18 - 2r + 4r = 18 + 2r = 18 + 2(3) = 18 + 6 = 24
Please help it’s kinda confusing only got 20 minutes left !!
Identify the domain of the function shown in the graph.
A researcher believes that 9% of males smoke cigarettes. If the researcher is correct, what is the probability that the proportion of smokers in a sample of 664 males would differ from the population proportion by greater than 3%
Answer:
0.0070 = 0.70% probability that the proportion of smokers in a sample of 664 males would differ from the population proportion by greater than 3%
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
A researcher believes that 9% of males smoke cigarettes.
This means that [tex]p = 0.09[/tex]
Sample of 664
This means that [tex]n = 664[/tex]
Mean and standard deviation:
[tex]\mu = p = 0.09[/tex]
[tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\frac{0.09*0.91}{664}} = 0.011[/tex]
What is the probability that the proportion of smokers in a sample of 664 males would differ from the population proportion by greater than 3%?
Proportion below 9 - 3 = 6% or above 9 + 3 = 12%. Since the normal distribution is symmetric, these probabilities are equal, so we find one of them and multiply by 2.
Probability the proportion is below 6%
P-value of Z when X = 0.06. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.06 - 0.09}{0.011}[/tex]
[tex]Z = -2.7[/tex]
[tex]Z = -2.7[/tex] has a p-value of 0.0035
2*0.0035 = 0.0070
0.0070 = 0.70% probability that the proportion of smokers in a sample of 664 males would differ from the population proportion by greater than 3%
In ABC, if CB AC≅ , m∠A = 3x + 18, m∠B = 7x – 58, and m∠C = 2x – 8, find x and the measure of each angle.
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Answer:
x = 19
A = 30°
B = C = 75°
Step-by-step explanation:
In an isosceles triangle, the angles opposite the congruent sides have the same measures.
A = B
3x +18 = 7x -58
76 = 4x . . . . . . . . add 58-4x
19 = x . . . . . . . . . divide by 4
Then the equal angles measure ...
A = B = 3(19) +18 = 75
C = 2(19) -8 = 30
Angles A, B, C measure 75°, 75°, 30°, respectively.
_____
Alternate solution
The sum of angles in a triangle is 180°, so you could write ...
(3x +18) +(7x -58) +(2x -8) = 180
12x = 228 . . . . . add 48
x = 19 . . . . . divide by 12
A telephone exchange operator assumes that 7% of the phone calls are wrong numbers. If the operator is accurate, what is the probability that the proportion of wrong numbers in a sample of 459 phone calls would differ from the population proportion by more than 3%
Answer:
0.0118 = 1.18% probability that the proportion of wrong numbers in a sample of 459 phone calls would differ from the population proportion by more than 3%
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
A telephone exchange operator assumes that 7% of the phone calls are wrong numbers.
This means that [tex]p = 0.07[/tex]
Sample of 459 phone calls:
This means that [tex]n = 459[/tex]
Mean and standard deviation:
[tex]\mu = p = 0.07[/tex]
[tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\sqrt{\frac{0.07*0.93}{459}}} = 0.0119[/tex]
What is the probability that the proportion of wrong numbers in a sample of 459 phone calls would differ from the population proportion by more than 3%?
Proportion below 0.07 - 0.03 = 0.04 or above 0.07 + 0.03 = 0.1. Since the normal distribution is symmetric, these probabilities are the same, which means that we find one of them and multiply by 2.
Probability the proportion is below 0.04.
p-value of Z when X = 0.04. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.04 - 0.07}{0.0119}[/tex]
[tex]Z = -2.52[/tex]
[tex]Z = -2.52[/tex] has a p-value of 0.0059
2*0.0059 = 0.0118
0.0118 = 1.18% probability that the proportion of wrong numbers in a sample of 459 phone calls would differ from the population proportion by more than 3%
The following data were obtained from 4 people Pre-Test Value Post-test Value 43 42 28 29 31 30 28 25 You may also assume that the sample standard deviation for the four differences is 1.6. What is the correct t-statistic and the degrees of freedom for these data
Answer:
Test statistic = 1.25
Degree of freedom = 3
Step-by-step explanation:
The following data were obtained from 4 people
Pre-Test Value Post-test Value __ d
43 ________42 _________ 1
28_______ 29 ________ - 1
31 ________30 _________ 1
28 ________ 25 _________ 3
μd = (1 + - 1 + 1 + 3) / 4 = 4 /4 = 1
The mean difference, μd = 1
The standard deviation of difference, Sd = 1.6
The test statistic = μd / (Sd / √n)
Test statistic = 1 / (1.6/2) = 1 / 0.8
Test statistic = 1.25
Degree of freedom, = n - 1 = 4 - 1 = 3
Side CA of the right triangle CAT is 3cm long. The hypotenuse is 5cm long. How many
square centimeters is the area of CAT?
Answer:
8
Step-by-step explanation:
By taking the number "3" and plus together with the number 5
What is the length of an arc with a central angle of 2/3pi radians and a radius of 24 centimeters?
Use 3.14 for pi.
Enter your answer, as a decimal, in the box.
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Answer:
50.24 cm
Step-by-step explanation:
Fill in the given numbers and do the arithmetic.
s = rθ
s = (24 cm)(2/3π) = (24 cm)(2/3)(3.14) = 50.24 cm
A sample of 24 observations is taken from a population that has 150 elements. The sampling distribution of is _____. an. approximately normal because is always approximately normally distributed b. approximately normal because the sample size is large in comparison to the population size c. approximately normal because of the central limit theorem d. normal if the population is normally distributed
Answer:
d. normal if the population is normally distributed
Step-by-step explanation:
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
In this question:
Sample size less than 30, so only will be normal if the population is normally distribution, and thus the correct answer is given by option d.
Lightbulbs. A company produces lightbulbs. We know that the lifetimes (in hours) of lightbulbs follow a bell-shaped (symmetric and unimodal) distribution with a mean of 7,161 hours and a standard deviation of 564 hours. Use the Empirical Rule (68-95-99.7 rule) to answer the following question: The shortest lived 2.5% of the lightbulbs burn out before how many hours
Answer:
Please find the complete question and its solution in the attached file.
Step-by-step explanation:
Shortest had survived after 6741 hours [tex]2.5\%[/tex] of the lights burnt.
[tex]\to 0.15\% + 2.35\% = 2.50\%[/tex]
Help plz I just need the awnser to this question
Answer:
A seems to be correct
Step-by-step explanation:
Complete the angle addition postulate for the following angle
Answer:
measurement m<GEM+m<MEO=m<GEO
a. 23 = -11 - 4x
b. 23 = -11 + (-4x)
C. 23 + 11 = -11 + (-4x) + 11
d. 23 + 11 = -11 + 11 +(-4x)
e. 34 = - 4x
f. 34/-4 = -4x/ -4
g. -8.5 = x
Which properties of equality justify steps c and f?
A.) addition property of equality; subtraction property of equality B.) addition property of equality; division property of equality C.) subtraction property of equality; multiplication property of equality D.) multiplication property of equality; division property of equality
Answer:
B.) addition property of equality; division property of equality
HW HELP ASAP PLZZZZZ
Answer:
p = 15/x
x= -3
Step-by-step explanation:
For the first problem, we can expand the equation to 4px+4=64
then simplify it to:
4px=60
then divide 4x from both sides of the equation
p=60/4x
then simplify:
p=15/x
For the second problem:
plug in -5 for p so the equation would look like
4(-5x +1)=64
simplify
-20x=60
x= -3
Sam thinks of a 4 digit number. The digit in the one’s place is 3 less than the digit in the ten’s place and digit in thousand’s place is 5 less than the digit in hundred’s place. The value of the hundred’s place is 800. The digit in ten’s place is the greatest even number. What is the number Sam is thinking of?
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Answer:
3885
Step-by-step explanation:
The hundreds digit is 8, and the thousands digit is 5 less, so is 3.
The tens digit is 8 (the largest even digit), and the ones digit is 3 less, so is 5.
The number is ...
3885
The solution set of the inequality 1 + 2y
Answer:
is it four I am not quite sure
The polynomial 3x² + mx? - nx - 10 has a factor of (x - 1). When divided by x + 2, the remainder is 36. What are
the values of m and n?
Answer:
[tex]m = 12[/tex]
[tex]n =3[/tex]
Step-by-step explanation:
Given
[tex]P(x) = x^3 + mx^2 - nx - 10[/tex]
Required
The values of m and n
For x - 1;
we have:
[tex]x - 1 = 0[/tex]
[tex]x=1[/tex]
So:
[tex]P(1) = (1)^3 + m*(1)^2 - n*(1) - 10[/tex]
[tex]P(1) = 1 + m*1 - n*1 - 10[/tex]
[tex]P(1) = 1 + m - n - 10[/tex]
Collect like terms
[tex]P(1) = m - n + 1 - 10[/tex]
[tex]P(1) = m - n -9[/tex]
Because x - 1 divides the polynomial, then P(1) = 0;
So, we have:
[tex]m - n -9 = 0[/tex]
Add 9 to both sides
[tex]m - n = 9[/tex] --- (1)
For x + 2;
we have:
[tex]x + 2 = 0[/tex]
[tex]x = -2[/tex]
So:
[tex]P(-2) = (-2)^3 + m*(-2)^2 - n*(-2) - 10[/tex]
[tex]P(-2) = -8 + 4m + 2n - 10[/tex]
Collect like terms
[tex]P(-2) = 4m + 2n - 10 - 8[/tex]
[tex]P(-2) = 4m + 2n - 18[/tex]
x + 2 leaves a remainder of 36, means that P(-2) = 36;
So, we have:
[tex]4m + 2n - 18 = 36[/tex]
Collect like terms
[tex]4m + 2n = 36+18[/tex]
[tex]4m + 2n = 54[/tex]
Divide through by 2
[tex]2m + n=27[/tex] --- (2)
Add (1) and (2)
[tex]m + 2m - n + n = 9 +27[/tex]
[tex]3m =36[/tex]
Divide by 3
[tex]m = 12[/tex]
Substitute [tex]m = 12[/tex] in (1)
[tex]m - n =9[/tex]
Make n the subject
[tex]n = m - 9[/tex]
[tex]n = 12 - 9[/tex]
[tex]n =3[/tex]
Roulette is a casino game that involves spinning a ball on a wheel that is marked with numbered squares that are red, black, or green. Half of the numbers 1 - 36 are colored red and half are black and the numbers 0 and 00 are green. Each number occurs only once on the wheel. What is the probability of landing on an even number and a number greater than 17? (A number is even if it is divisible by 2. 0 and 00 are considered even as well.)
Answer:
the wording (punctuation) of the question can lead to different interpretations....
I assume that the question was >17 & even which is "5/19",
BUT... it can also be read as two questions
first >17 which is "10/19"
and second an even number which is "9/19"
BUT !!! I think that the question answer is 5/19
Step-by-step explanation:
Even Number = 18/38 = 9/19
greater 17 = 20/38 = 10/19
Even & greater 17 = 10/38 = 5/19
Tim Hortons is hiring and offers $200 every week plus $5 per hour. McDonalds offers $300 every week plus $2 per hour. State the conditions under which Tim Hortons is the better employer
Answer:
Assuming you want better payment each week, any number of hours above 33.333 or 33 hours and 20 minutes per week
Step-by-step explanation:
There are several ways we could do this. We could say we want to have Tim Hortons be the better employer on the first week, or after so many weeks by adjusting the hours. I am going to assume we are saying we want it to be a better employer on the first week, so the profit will be the amount made every week plus the money made per hour times the number of hours.
Let's say number of hours is H
So Tim Hortons winds up as 200 + 5H for one week and Mcdonalds will be 300 + 2H.
If you set the two expressions equal to each other you will find where they intersect, which means at that number of hours they will give the same amount of money while any amount before one of the companies will give more and after that many hours the other will. Let's go ahead and solve.
200 + 5H = 300 + 2H
3H = 100
H = 100/3
So H is about 33.333. let's check.
200 + 5(33.333) = 366.665 which rounds to 366.67 dollars
300 + 2(33.333) = 366.666 which also rounds to 366.67 dollars
So at 33.333 hours both give 366.67 dollars. Let's look at a value below it, say 32.
200 + 5(32) = 360
300 + 2(32) = 364
So you can see here Tim Hortons pays less. Now we will try 34 as a value above 33.333
200 + 5(32) = 370
300 + 2(32) = 368
Here Mcdonalds pays less. This was to show that values below 33.333 make Tim Hortonspay less and values above 33.333 make Mcdonalds pay less. In other words any value above 33.333 hours will have Tim Hortons be the better employer. And this is per week
I want to repeat, you can expand this to be multiple weeks and see which of the two becomes better in that epriod of time. This was, I think, the simplest way to answer though.
So the conditions where Tim Horton pays more isif you work more than 33.333 hours per week. This will make them pay more every single week.
I need help with this question
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Answer:
x = 22, y = 123
Step-by-step explanation:
The sum of angles in a triangle is 180°.
(2x +13)° +57° +3x° = 180°
5x +70 = 180 . . . . . . . . . . . . . collect terms, divde by °
5x = 110 . . . . . . . . . . . subtract 70
x = 22 . . . . . . . . divide by 5
__
Angles in a linear pair are supplementary.
y° + 57° = 180°
y = 123 . . . . . . . . divide by °, subtract 57
9 friends are lining up. Joe, Susan, John, and Meredith must be beside each other. How many ways can they line up?
This is one single number slightly over 17 thousand.
You may need to erase the comma when typing the answer in.
=========================================================
Explanation:
Let's say that another person steps in for Joe, Susan, John, and Meredith. I'll refer to this person as the teacher (perhaps these 9 friends are students on a field trip).
The 9 friends drops to 9-4 = 5 people when those four named people leave the group temporarily. Then it bumps up to 5+1 = 6 people when the teacher steps in. Wherever the teacher is located, the four friends that left will replace the teacher. This guarantees that those four friends stick together.
There are 6! = 6*5*4*3*2*1 = 720 ways to arrange those 6 people. The exclamation mark is a factorial symbol.
Within any of those 720 permutations, we have 4! = 4*3*2*1 = 24 ways to arrange those group of named people when they come back to replace the teacher.
So overall the answer is 4!*6! = 24*720 = 17,280
You may need to erase the comma when typing the answer in.
-------------
Side note: There are 9! = 362,880 ways to arrange all nine friends regardless if those four mentioned people stick together or not. We see that they stick together roughly (17,280)/(362,880) = 0.0476 = 4.76% of the time.
I want my answer please help
Answer:
This is pretty simple
Step-by-step explanation:
So the only thing you need to know about negatives and positives is that if your multiplying or dividing a number with 1 negative in the expreession/equation The answer will always result in a negative. If its 2 negatives its always positive. Thats all you need to know and then just solve it from there.
Answer:
See explanation and picture below.
Step-by-step explanation:
In both multiplication and division of 2 numbers, different signs give you negative and equal signs give you positive.
In other words, positive & positive or negative and negative give you a positive answer.
Negative and positive or positive and negative give you negative answer.
Graph 9x + 15y = 15.
Solve the simultaneous equations
6
x
+
2
y
=
12
5
x
+
2
y
=
8
Answer: x=4, y=-6
Step-by-step explanation:
the cost of 7 shirts is $63. find the cost of 5 shirts
1. $35
2. $45
3. $52
4. $70
Find the values of X and Y that makes these triangles congruent by the HL theorem
Answer:
C. x = 3, y = 2
Step-by-step explanation:
If both triangles are congruent by the HL Theorem, then their hypotenuse and a corresponding leg would be equal to each other.
Thus:
x + 3 = 3y (eqn. 1) => equal hypotenuse
Also,
x = y + 1 (eqn. 2) => equal legs
✔️Substitute x = y + 1 into eqn. 1 to find y.
x + 3 = 3y (eqn. 1)
(y + 1) + 3 = 3y
y + 1 + 3 = 3y
y + 4 = 3y
y + 4 - y = 3y - y
4 = 2y
Divide both sides by 2
4/2 = 2y/2
2 = y
y = 2
✔️ Substitute y = 2 into eqn. 2 to find x.
x = y + 1 (eqn. 2)
x = 2 + 1
x = 3
Find a power series representation for the function. (Assume a>0. Give your power series representation centered at x=0 .)
f(x)=x2a7−x7
Answer:
Step-by-step explanation:
Given that:
[tex]f_x = \dfrac{x^2}{a^7-x^7}[/tex]
[tex]= \dfrac{x^2}{a^7(1-\dfrac{x^7}{a^7})}[/tex]
[tex]= \dfrac{x^2}{a^7}\Big(1-\dfrac{x^7}{a^7} \Big)^{-1}[/tex]
since [tex]\Big((1-x)^{-1}= 1+x+x^2+x^3+...=\sum \limits ^{\infty}_{n=0}x^n\Big)[/tex]
Then, it implies that:
[tex]\implies \dfrac{x^2}{a^7} \sum \limits ^{\infty}_{n=0} \Big(\Big(\dfrac{x}{a} \Big)^{^7} \Big)^n[/tex]
[tex]= \dfrac{x^2}{a^7} \sum \limits ^{\infty}_{n=0} \Big(\dfrac{x}{a} \Big)^{^{7n}}[/tex]
[tex]= \dfrac{x^2}{a^7} \sum \limits ^{\infty}_{n=0} \Big(\dfrac{x^{7n}}{a^{7n}} \Big)}[/tex]
[tex]\mathbf{= \sum \limits ^{\infty}_{n=0} \dfrac{x^{7n+2}}{a^{7n+7}} }}[/tex]