Answer:
A) k=1
Step-by-step explanation:
5-k+12=16
17-k=16
k=1
Answer:
k=1
Step-by-step explanation:
5-k+12=16
Combine like terms
17 - k = 16
Subtract 17 from each side
17-k-17 = 16-17
-k = -1
Divide by -1
k = 1
Please help . I’ll mark you as brainliest if correct !
Answer:
4 ( a+2)
Step-by-step explanation:
The average rate of change is
(f(a) - f(2))/(a-2)
f(a) = 4a^2 -8
f(2) = 4*2^2 -8 = 4*4 -8 = 16-8 = 8
(4a^2 - 8 - 8))/(a-2)
(4a^2 -16) / (a-2)
Factor the numerator
4( a^2 -4) / (a-2)
4( a-2)(a+2) / (a-2)
Cancel
4 ( a+2)
Which one of the following is always true?a. The coefficient of variation measures variability in a positively skewed data set relative to the size of the median.b. None of the suggested answers are correctc. The coefficient of variation is a measure of relative dispersion that expresses the standard deviation as a percentage of the mean, for any data on a ratio scale and an interval scale.d. The interquartile range is very unique in the sense that it is a measure of central tendency as well as a measure of dispersion.e. The coefficient of variation should only be used to compare positive data on an interval scale.
Answer:
C. The coefficient of variation is a measure of relative dispersion that expresses the standard deviation as a percentage of the mean, for any data on a ratio scale and an interval scale
Step-by-step explanation:
Th Coefficient of Variance is a measure of dispersion that can be calculated using the formula:
[tex]CV = \frac{\sigma_{x} }{\mu_{x} } * 100%[/tex]
Where [tex]\sigma{x}[/tex] is the Standard Deviation
and [tex]\mu_{x}[/tex] is the sample mean
From the formula written above, it is shown that the Coefficient of Variation expresses the Standard Deviation as a percentage of the mean.
Coefficient of variation can be used to compare positive as well as negative data on the ratio and interval scale, it is not only used for positive data.
The Interquartile Range is not a measure of central tendency, it is a measure of dispersion.
Simplify (4.5)(5)(-2)
Answer:
[tex] - 45[/tex]
[tex]2.25( - 2) = - 45 \\ - 45[/tex]
Please help me on this
Answer19/40=x/3.6
By cross multiplication
19*3.6=40*x
68.4 =40x
x=68.4/40
x=1.71
x=
Answer: C
Step-by-step explanation:
[tex]\frac{19}{40} = \frac{x}{3.6}[/tex] solve by cross product
40x = 68.4 Divide both sides by 40
x = 1.71
A store, on average, has 500 customers per day.
a) what can be said about the probability that it will have at least 700 customers on a given day?
from now on, suppose in addition that the variance of the numbers of customers per day is 100.
b) what can be said about the probability that it will have at least 700 customers on a given day?
c) what can be said about the probability that there will be more than 475 and less than 525 customers on a given day?
Answer:
a) We can not estimate the probability.
b) Zero probability.
c) There is a probability between 95% and 99% that they have between 475 and 525 customers on a given day.
Step-by-step explanation:
a) We can not said nothing because we only know the average of customers per day. We need to know the probability distribution of the amount of customers per day to answer this question.
b) Now that we know that the variance is 100, although we do not know the exact distribution of the values, we can use the empirical rules to estimate the probability of having at least 700 customers on a given day.
If the variance is 100, the standard deviation is √100=10.
Applying the empirical rule (68-95-99.7 rule), we know that there is probability 0.15% of having at least 500+3*10=530 customers per day (more than 3 deviations from the mean).
Then, we can conclude that the probability of having at least 700 customers per day is zero.
c) To estimate this probability, we have to calculate how many deviations from the mean this values represent:
[tex]\Delta_1=475-500=-25=2.5\sigma\\\\\Delta_2=525-500=25=2.5\sigma[/tex]
We have an interval that have a width of ±2.5 deviations from the mean.
For 2 deviations from the mean, it is expected to have 95% of the data.
For 3 deviations from the mean, it is expected to have 99.7% of the data.
Then, for the interval 475 to 525, we can estimate a probability between 95% and 99%.
A tank contains 24 gallons of water when all of a sudden the water begins draining at a constant rate of 2 gallons per hour. Let t represent the number of hours since the water began draining and let v represent the volume of water in the tank.
Required:
a. Write a formula that expresses v in terms of t.
b. As t increases from 3 to 6, v varies from _________ to _________
Answer:
a) [tex]V(t) = 24 - 2t[/tex]
b) As t increases from 3 to 6, v varies from 18 gallons to 12 gallons.
Step-by-step explanation:
The volume of the tank in terms of the time can be described by the following equation:
[tex]V(t) = V(0) - at[/tex]
In which V(0) is the initial volume and a is the hourly decrease rate.
a. Write a formula that expresses v in terms of t.
The tank initially contains 24 gallons of water, which means that [tex]V(0) = 24[/tex]
Drains at a constant rate of 2 gallons per hour, so [tex]a = 2[/tex]
Then
[tex]V(t) = V(0) - at[/tex]
[tex]V(t) = 24 - 2t[/tex]
b. As t increases from 3 to 6, v varies from _________ to _________
[tex]V(t) = 24 - 2t[/tex]
[tex]V(3) = 24 - 2*3 = 18[/tex]
[tex]V(6) = 24 - 2*6 = 12[/tex]
So as t increases from 3 to 6, v varies from 18 gallons to 12 gallons.
What is the y-intercept of a line that has a slope of -3 and passes through point (0, -7)?
Answer:
Step-by-step explanation:
line equation: y=mx + C
substitute given values
-7 = -3*0 + C
C=y= -7 ANS
What’s the correct answer for this question?
Answer:
A
Step-by-step explanation:
Volume of cone = (1/3) πr²h
Solve for x in the diagram below
Answer:
So the diagram couldn't come due to coronavirus?
Answer:
there is no diagram
Step-by-step explanation:
Two voting districts, C and M, were sampled to investigate voter opinion about tax spending. From a random sample of 100 voters in District C, 22 percent responded yes to the question "Are you in favor of an increase in state spending on the arts?" An independent random sample of 100 voters in District M resulted in 26 percent responding yes to the question. A 95 percent confidence interval for the difference
Answer:
Step-by-step explanation:
Confidence interval for the difference in the two proportions is written as
Difference in sample proportions ± margin of error
Sample proportion, p= x/n
Where x = number of success
n = number of samples
For district C,
x = 22
n1 = 100
p1 = 22/100 = 0.22
For district M,
x = 26
n2 = 100
p2 = 26/100 = 0.26
Margin of error = z√[p1(1 - p1)/n1 + p2(1 - p2)/n2]
To determine the z score, we subtract the confidence level from 100% to get α
α = 1 - 0.95 = 0.05
α/2 = 0.05/2 = 0.025
This is the area in each tail. Since we want the area in the middle, it becomes
1 - 0.025 = 0.975
The z score corresponding to the area on the z table is 1.96. Thus, the z score for the confidence level of 95% is 1.96
Margin of error = 1.96 × √[0.22(1 - 0.22)/100 + 0.26(1 - 0.26)/100]
= 1.96 × √0.00364
= 0.12
Confidence interval = (0.22 - 0.26) ± 0.12
= - 0.04 ± 0.12
The required 95 percent confidence interval for the difference is ( 0.8, 0.16).
Given that,
A random sample of 100 voters in District C, 22 percent responded yes to The question "Are you in favor of an increase in state spending on the arts?"
An independent random sample of 100 voters in District M resulted in 26 percent responding yes to the question.
We have to determine,
A 95 percent confidence interval for the difference.
According to the question,
A random sample of 100 voters in District C, 22 percent responded yes to The question "Are you in favor of an increase in state spending on the arts?"
An independent random sample of 100 voters in District M resulted in 26 percent responding yes to the question.
Confidence interval for the difference in the two proportions is written as,
Difference in sample proportions ± margin of error
Sample proportion, p= x/n
Where x = number of success
n = number of samples
From a random sample of 100 voters in District C,
[tex]x = 22\\\\n_1= 100\\\\p_1 = \dfrac{22}{100} = 0.22[/tex]
From a random sample of 100 voters in District M,
[tex]x = 26\\\\n_1= 100\\\\p_1 = \dfrac{26}{100} = 0.26[/tex]
Therefore,
[tex]Margin \ of \ error = \sqrt{\dfrac{p_1(1-p_1}{n_1} + \dfrac{p_2(1-p_2)}{n_2}}[/tex]
To determine the z score, subtract the confidence level from 100% to get b
α = 1 - 0.95 = 0.05
α/2 = 0.05/2 = 0.025
This is the area in each tail. Since, the area in the middle, it becomes
1 - 0.025 = 0.975
The z-score corresponding to the area on the z table is 1.96. Thus, the z score for the confidence level of 95% is 1.96,
[tex]Margin \ of \ error = \sqrt{\dfrac{0.22(1-0.22)}{100} + \dfrac{0.26(1-0.26)}{100}}[/tex]
[tex]= \sqrt{\dfrac{0.22(0.78)}{100} +\dfrac{0.26(0.76)}{100}}\\\\= \sqrt{\dfrac{0.17}{100}+ \dfrac{0.19}{100}}\\\\= \sqrt{\dfrac{0.36}{100}}\\\\= \sqrt{0.0036}\\\\= 0.06[/tex]
Then, Confidence interval is given as;
[tex](0.22 - 0.26) \pm 0.12\\\\(-0.4) \pm 0.12\\\\(-0.4+0.12 , -0.4-0.12)\\\\(0.8, 0.16)[/tex]
Hence, The required 95 percent confidence interval for the difference is( 0.8, 0.16)
To know more about Confidence interval click the link given below.
https://brainly.com/question/15349022
Find the midpoint of (9,2) and (-7,-9)
Answer:
(1,-7/2)
Step-by-step explanation:
The midpoint of (9,2)(-7,-9) is (1,-7/2)
A small child has 6 more quarters than nickels. If the total amount of the coins is $3.00, find the number of nickels and quarters the child has.
Answer:
nickels- 5, quarters- 11
Step-by-step explanation:
nickel= 5 p, quarter= 25 p
5x+25(x+6)= 300
30x+150=300
30x=150
x=150/30
x=5 nickels
x+6= 11 quarters
Patricia can buy individual songs for $1.00 to download. Also, an entire album costs $10.00 to download. She can spend no more than a total of $80. She wants to buy no more than four albums, and at least 30 individual songs. The following system of inequalities represents this situation, where x is the number of individual songs and y is the number of albums.
Answer:
The system of inequalities is:
[tex]x\geq30\\\\y\leq4\\\\10x+1y\leq80[/tex]
Step-by-step explanation:
We will write each of the conditions stated in this problem
Patricia wants to buy at least 30 individual songs.
[tex]x\geq30[/tex]
She wants to buy 4 albums at most.
[tex]y\leq4[/tex]
The total expenditure has to be equal or less than $80, when each album cost $10 and each individual song cost $1.
[tex]10x+1y\leq80[/tex]
The system of inequalities is:
[tex]x\geq30\\\\y\leq4\\\\10x+1y\leq80[/tex]
Could someone please help me with the steps for this problem? Factor by grouping: w²+3w+w+3
Answer:
Please see steps below
Step-by-step explanation:
In order to factor by grouping, we divide the four terms given into two groups, and extract on each group any common factor we can.
In our example, we can select the terms: [tex]w^2[/tex] and [tex]w[/tex] as one of our groups, and [tex]3w[/tex] and 3 in the other group. Then we re-organize the expression as:
[tex](w^2+w)+(3x+3)[/tex]
Now we extract from the first binomial group, the factor [tex]w[/tex] as a common factor of both terms, and from the second group we extract the factor "3" as common factor of those two terms:
[tex](w^2+w)+(3x+3)\\w(w+1)+3(w+1)[/tex]
We notice now that after the extraction, we are left with two exactly equal binomial factors [tex](w+1)[/tex] that appeared in the first group and in the second group. We proceed then to extract it as common factor for the two groups:
[tex]w(w+1)+3(w+1)\\(w+1)(w+3)[/tex]
this last product of two binomials ([tex](w+1)\,(w+3)[/tex] is the result of factoring the original expression.
A random sample of adult female reaction times has a sample mean of x¯=394.3 milliseconds and sample standard deviation of s=84.6 milliseconds. Use the Empirical Rule to determine the approximate percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds.
Answer:
The percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds is 99.7%.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 394.3 ms
Standard deviation = 84.6 ms
Use the Empirical Rule to determine the approximate percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds.
140.5 = 394.3 - 3*84.6
So 140.5 is 3 standard deviations below the mean.
648.1 = 394.3 + 3*84.6
So 648.1 is 3 standard deviations above the mean.
By the Empirical Rule,
The percentage of adult female reaction times that lie between 140.5 and 648.1 milliseconds is 99.7%.
Jose predicted that he would sell 48 umbrellas. He actually sold 72 umbrellas.What are the values of a and b in the table below. Round to the nearest tenth if necessary
Answer:
The answer is A
Step-by-step explanation:
1)Twelve years ago Jane was five times as old as Anne. In three years time,Anne will be half Jane's age How old is each girl at the moment
Answer:
Step-by-step explanation:
Twelve years ago Jane was five times as old as Anne.
J-12=5(A-12)
In three years time, Anne will be half of Jane's age.
A+3=1/2(J+3)
Simplify and solve this system of equations:
J-12=5(A-12)
A+3=1/2(J+3)
g(-4)
Please help!!
Answer:
1
Step-by-step explanation:
g(-4) means what is the y value when x is -4.
Find x=-4, and when x=-4. y=1
Answer:
1
Step-by-step explanation:
15 POINTS & BRAINLIEST!!!
How do you find the axis of symmery in the form f(x) = 3(x - 4)^2 + 5?
Answer:
so the axis of symmetry is x=4
Answer: X = 4
Explanation: Hope it helps you♡
You are situated 300 feet from the base of Tower Glitz Plaza watching an external elevator descend down the side of the building. At a certain instant the elevator is 500 feet away from you, and its distance from you is decreasing at a rate of 16 ft/sec. How fast is the elevator descending at that instant?
Answer:
18.66 ft/s
Step-by-step explanation:
The distance between you and the elevator is given by:
[tex]h=\sqrt{x^2+y^2}[/tex]
The rate of change for the distance between you and the elevator is given by:
[tex]\frac{dh}{dt}=\frac{dh}{dy}*\frac{dy}{dt}[/tex]
[tex]-16=\frac{dh}{dy}*\frac{dy}{dt}[/tex]
[tex]\frac{dh}{dy}=\frac{d}{dy} (\sqrt{x^2+y^2})\\[/tex]
Applying the chain rule:
[tex]u=x^2+y^2\\\frac{dh}{dy}=\frac{d\sqrt u}{du} *\frac{du}{dy}\\\frac{dh}{dy}=\frac{1}{2\sqrt u} *2y\\\frac{dh}{dy}=\frac{y}{\sqrt {(x^2+y^2)}}[/tex]
Therefore, at x=300 and y = 500, dy/dt is:
[tex]-16=\frac{y}{\sqrt {(x^2+y^2)}}*\frac{dy}{dt}\\-16=\frac{500}{\sqrt {(300^2+500^2)}}*\frac{dy}{dt}\\\frac{dy}{dt}=-18.66\ ft/s[/tex]
The elevator is descending at 18.66 ft/s.
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer:
B. (f - g)(x) = [tex]3^x-2x+14[/tex]
Step-by-step explanation:
→Set it up, like so:
[tex](3^x+10)-(2x-4)[/tex]
→Distribute the -1 to (2x - 4):
[tex]3^x+10-2x+4[/tex]
→Add like terms (10 and 4):
[tex]3^x-2x+14[/tex]
The relationship between ttt and rrr is expressed by the equation 2t+3r+6=02t+3r+6=02, t, plus, 3, r, plus, 6, equals, 0. If rrr increases by 444, which of the following statements about ttt must be true?
Question:
The relationship between t and r is expressed by the equation 2t+3r+6 = 0. If r increases by 4, which of the following statements about t must be true?
Answer:
The value of t is reduced by 6 when the value of r is increased by 4
Step-by-step explanation:
Given
[tex]2t + 3r + 6 = 0[/tex]
Required
What happens when r is increased by 4
[tex]2t + 3r + 6 = 0[/tex] -------- Equation 1
Subtract 2t from both sides
[tex]2t + 3r + 6 - 2t = 0 - 2t[/tex]
[tex]3r + 6 = - 2t[/tex] --- Equation 2
When r is increased by 4, equation 1 becomes
[tex]2T + 3(r+4) + 6 = 0[/tex]
Note that the increment of r also affects the value of t; hence, the new value of t is represented by T
Open bracket
[tex]2T + 3r+12 + 6 = 0[/tex]
Rearrange
[tex]2T + 3r+6 +12 = 0[/tex]
Substitutr -2t for 3r + 6 [From equation 2]
[tex]2T -2t +12 = 0[/tex]
Make T the subject of formula
[tex]2T = 2t - 12[/tex]
Divide both sides by 2
[tex]\frac{2T}{2} = \frac{2t - 12}{2}[/tex]
[tex]T = t - 6[/tex]
This means that the value of t is reduced by 6 when the value of r is increased by 4
(a^2-b^2) (c^2-d^2) +4abcd
[tex]a^{2} {c}^{2} - {a}^{2} {d}^{2} - {b}^{2} {c}^{2} + {b}^{2} {d}^{2} + 4abc[/tex]
plz answer this asap
Answer: 20
Step-by-step explanation: 5 times 4 is 20 times 2 is 40, but when you divide by 1/2 you drop down to 20.
Alex is planning to surround his pool ABCD with a single line of tiles. How many units of tile will he need to surround his pool? Round your answer to the nearest hundredth.
Answer:
19.82 units
Step-by-step explanation:
The number of units of tile simply refers to the perimeter.
So, we need to find all the sides of the rectangle.
Now, we have AB = 4.24 units and BD = 7.07 units.
So, we can find AD using pythagoras theorem.
So,
(AD)² + 4.24² = 7.07²
(AD)² + 17.978 = 49.985
(AD)² = 49.985 - 17.978
AD = √32.007
AD = 5.66 units
AD = BC = 5.66 units
Likewise, AB = DC = 4.24 units
Thus,
perimeter = 2(5.66) + 2(4.24) = 19.8 units
Closest answer among the options is approximately 19.82
Answer:
19.82 units
Step-by-step explanation:
just took test and got it right
Able, ben and cal each played a game.
able scored six times bens score.
cal scored a third of able's score. write down the ratio of able's score to ben;s score to cal's score
Answer:
Ratio of Able's score to Ben=6:1
Ratio of Ben's score to Cal's=1:2
Ratio of able's score to ben;s score to cal's score=6:1:2
Step-by-step explanation:
Let Ben's score =x
Able scored six times Ben's score
Able=6*x
=6x
Cal scored a third of Able's score
Cal=1/3 of 6x
=1/3(6x)
Ratio of Able's score to Ben
6x:x
=6:1
Ratio of Ben's score to Cal's score
x:1/3(6x)
=x:6x/3
=x:2x
=1:2
Ratio of able's score to ben;s score to cal's score=6:1:2
A farmer knows that every 50 eggs his chickens lay, only 45 will be marketable. If his
chickens lay 1000 eggs in a week, how many of them will be marketable?
Answer:
900 eggs
Step-by-step explanation:
45/50 are marketable
divide the top and bottom by 5
9/10
Multiply this fraction by the 1000 eggs laid
9/10 *1000
900 eggs will be marketable
Answer:
900
Step-by-step explanation:
Alex has a bag of stuffed animals containing nine bears, six lions, and three monkeys. The probability that Alex will randomly pull out a bear and then a lion is . Using this probability, determine if the event of pulling out a bear and the event of pulling out a lion was independent, dependent, both, or neither.
Answer:
P = 0.1764
The events are dependent
Step-by-step explanation:
We have a total of 9 + 6 + 3 = 18 stuffed animals.
The probability of the first animal pulled being a bear is:
P(bear) = N(bear) / N(total)
P(bear) = 9 / 18 = 0.5
Then, for the second animal, we now have only 17 stuffed animals in total.
So the probability of the second animal pulled being a lion, given the first animal was a bear, is:
P(lion | bear) = N(lion) / N(total)
P(lion | bear) = 6 / 17 = 0.3529
So the final probability is the product of these probabilities:
P = P(bear) * P(lion | bear) = 0.5 * 0.3529 = 0.1764
To find if the events are dependent or independent, let's find the probability of the first pick being a lion:
P(lion) = N(lion) / N(total)
P(lion) = 6 / 18 = 0.3333
The probability of picking a lion is different from the probability of picking a lion given we already picked a bear, so the events are dependent.
A U.S.-based Internet company offers an online proficiency course in basic accounting. Completing this online course satisfies the "Fundamentals of Accounting" course requirement in many MBA programs. In the first semester, 315 students have enrolled in the course. The marketing research manager divided the country into seven regions of approximately equal population. The course enrollment values for each of the seven regions are given below. The management wants to know if there is equal interest in the course across all regions. Region Enrollment 1 45 2 60 3 30 4 40 5 50 6 55 7 35 The CEO looked at the data presented and said no they are not equal. It is obvious, since the enrollment in one region is 60 and another 30. However, the CFO said that using a Chi-Square Goodness of Fit Test with a 1% significance level, the frequencies in the regions are not significantly different. Which one is correct? Use statistics to support your answer.
Answer:
[tex]Expected \ mean = \dfrac{sum \ of \ values }{n}[/tex]
[tex]Expected \ mean = \dfrac{315 }{7}[/tex]
Expected mean = 45
The Chi - Square Value = 15.556
Conclusion:
We conclude that there is equal number of average interest in the course across all regions.
Thus, the CFO is correct, the the frequencies in the regions are not significantly different by using a Chi-Square Goodness of Fit Test with a 1% significance level.
Step-by-step explanation:
From the question; Let state our null hypothesis and alternative hypothesis
Null Hypothesis
[tex]\mathbf{H_0:}[/tex]There is equal number of average interest in the course across all regions.
Alternative Hypothesis
[tex]\mathbf{H_a:}[/tex] At least one of the region differs in average number of interest in the course.
The table can be better structured as :
Region Enrollment
1 45
2 60
3 30
4 40
5 50
6 55
7 35
From above; we know the number of sample = 7
Then our expected mean can be calculated as :
[tex]Expected \ mean = \dfrac{sum \ of \ values }{n}[/tex]
[tex]Expected \ mean = \dfrac{315 }{7}[/tex]
Expected mean = 45
SO, let's construct our Chi-Square Statistics Test Table as follows:
Observed Expected Expected (O-E)² [tex]\dfrac{(O-E)^2}{E}[/tex]
(O) (E) proportion
45 45 0.142857 0 0
60 45 0.142857 225 5
30 45 0.142857 225 5
40 45 0.142857 25 0.556
50 45 0.142857 25 0.556
55 45 0.142857 100 2.222
35 45 0.142857 100 2.222
15.556
The Chi - Square Value = 15.556
Degree of freedom = n- 1
Degree of freedom = 7 - 1
Degree of freedom = 6
Level of significance ∝ = 1% = 0.01
The Critical value of Chi Square test statistic at df = 6 and 0.01 significance level is 16.812
The Decision rule is to reject the Null hypothesis if The Chi Square test statistic X² > 16.812
Thus , since the Chi Square test statistic is lesser than the critical value,
i.e 15.556 < 16.812 ,we accept null hypothesis [tex]\mathbf{H_0}[/tex]
Conclusion:
We conclude that there is equal number of average interest in the course across all regions.
Thus, the CFO is correct, the the frequencies in the regions are not significantly different by using a Chi-Square Goodness of Fit Test with a 1% significance level.
Find the range of the following data set.
11,5, 1, 11, 12
01
1.
017
Answer:
range 11
Step-by-step explanation:
The range is the largest number minus the smallest number
The largest number is 12 and the smallest number is 1
12 - 1 = 11