Answers
Answer:
x= -3
Step-by-step explanation:
2x+14= 8
2x= -6
x = -3
Answer:
-3
Step-by-step explanation:
According to the question,
[tex]\longrightarrow[/tex] CE = CD + DE
[tex]\longrightarrow[/tex] 8 = (x + 10) + (x + 4)
[tex]\longrightarrow[/tex] 8 = x + 10 + x + 4
[tex]\longrightarrow[/tex] 8 = 2x + 14
[tex]\longrightarrow[/tex] 8 ― 14 = 2x
[tex]\longrightarrow[/tex] ―6 = 2x
[tex]\longrightarrow[/tex] ―6 ÷ 2 = x
[tex]\longrightarrow[/tex] –3 = x
Therefore, the value of x is ― 3.
Related Questions
PLEASE HELP!!! Choose the best graph that represents the linear equation:
6x = y + 8
Graph A
On a coordinate plane, a line goes through (negative 2, 4) and (0, negative 8).
Graph B
On a coordinate plane, a line goes through (0, negative 8) and (2, 4).
Graph C
On a coordinate plane, a line goes through (negative 2, negative 4) and (0, 8).
Graph D
On a coordinate plane, a line goes through (0, 8) and (2, negative 4).
a.
Graph A
c.
Graph C
b.
Graph B
d.
Graph D
Please select the best answer from the choices provided
A
B
C
D
Answers
Answer:
b.
Graph B
Step-by-step explanation:
We are given the following linear equation:
[tex]6x = y + 8[/tex]
When x = 0:
[tex]6(0) = y + 8[/tex]
[tex]y = -8[/tex]
Thus, the line goes through (0,-8).
When y = 4:
[tex]6x = y + 8[/tex]
[tex]6x = 4 + 8[/tex]
[tex]6x = 12[/tex]
[tex]x = \frac{12}{6} = 2[/tex]
So also through (2,4).
Thus means that the correct answer is given by Graph B.
1. In the spring of 2017, the Consumer Reports National Research Center conducted a survey of 1007 adults to learn about their major health-care concerns. The survey results showed that 574 of the respondents lack confidence they will be able to afford health insurance in the future. Develop a 90% confidence interval for the population proportion of adults who lack confidence they will be able to afford health insurance in the future.
Answers
Answer:
The correct answer is "1668". A further solution is provided below.
Step-by-step explanation:
According to the question,
Estimated proportion,
[tex]\hat{p} = \frac{574}{1007}[/tex]
[tex]=0.57[/tex]
Margin of error,
E = 0.02
Level of confidence,
= 90%
= 0.90
Critical value,
[tex]Z_{0.10}=1.65[/tex]
Now,
⇒ [tex]0.02=1.65\times \sqrt{\frac{0.57\times 0.43}{n} }[/tex]
[tex]0.0004=2.7225\times \frac{0.2451}{n}[/tex]
[tex]n=\frac{2.7225\times 0.2451}{0.0004}[/tex]
[tex]=1668.21[/tex]
or,
[tex]n \simeq 1668[/tex]
find from first principle the derivative of 3x+5/√x
Answers
Answer:
[tex]\displaystyle \frac{d}{dx} = \frac{3x - 5}{2x^\bigg{\frac{3}{2}}}[/tex]
General Formulas and Concepts:
Algebra I
Exponential Rule [Powering]: [tex]\displaystyle (b^m)^n = b^{m \cdot n}[/tex]Exponential Rule [Rewrite]: [tex]\displaystyle b^{-m} = \frac{1}{b^m}[/tex] Exponential Rule [Root Rewrite]: [tex]\displaystyle \sqrt[n]{x} = x^{\frac{1}{n}}[/tex]Calculus
Derivatives
Derivative Notation
Derivative Property [Addition/Subtraction]: [tex]\displaystyle \frac{d}{dx}[f(x) + g(x)] = \frac{d}{dx}[f(x)] + \frac{d}{dx}[g(x)][/tex]
Basic Power Rule:
f(x) = cxⁿ f’(x) = c·nxⁿ⁻¹Derivative Rule [Quotient Rule]: [tex]\displaystyle \frac{d}{dx} [\frac{f(x)}{g(x)} ]=\frac{g(x)f'(x)-g'(x)f(x)}{g^2(x)}[/tex]
Step-by-step explanation:
Step 1: Define
Identify
[tex]\displaystyle \frac{3x + 5}{\sqrt{x}}[/tex]
Step 2: Differentiate
Rewrite [Exponential Rule - Root Rewrite]: [tex]\displaystyle \frac{3x + 5}{x^\bigg{\frac{1}{2}}}[/tex]Quotient Rule: [tex]\displaystyle \frac{d}{dx} = \frac{(x^\bigg{\frac{1}{2}})\frac{d}{dx}[3x + 5] - \frac{d}{dx}[x^\bigg{\frac{1}{2}}](3x + 5)}{(x^\bigg{\frac{1}{2}})^2}[/tex]Simplify [Exponential Rule - Powering]: [tex]\displaystyle \frac{d}{dx} = \frac{(x^\bigg{\frac{1}{2}})\frac{d}{dx}[3x + 5] - \frac{d}{dx}[x^\bigg{\frac{1}{2}}](3x + 5)}{x}[/tex]Basic Power Rule [Derivative Property - Addition/Subtraction]: [tex]\displaystyle \frac{d}{dx} = \frac{(x^\bigg{\frac{1}{2}})(3x^{1 - 1} + 0) - (\frac{1}{2}x^\bigg{\frac{1}{2} - 1})(3x + 5)}{x}[/tex]Simplify: [tex]\displaystyle \frac{d}{dx} = \frac{3x^\bigg{\frac{1}{2}} - (\frac{1}{2}x^\bigg{\frac{-1}{2}})(3x + 5)}{x}[/tex]Rewrite [Exponential Rule - Rewrite]: [tex]\displaystyle \frac{d}{dx} = \frac{3x^\bigg{\frac{1}{2}} - (\frac{1}{2x^{\frac{1}{2}}})(3x + 5)}{x}[/tex]Rewrite [Exponential Rule - Root Rewrite]: [tex]\displaystyle \frac{d}{dx} = \frac{3\sqrt{x} - (\frac{1}{2\sqrt{x}})(3x + 5)}{x}[/tex]Simplify [Rationalize]: [tex]\displaystyle \frac{d}{dx} = \frac{3x - 5}{2x^\bigg{\frac{3}{2}}}[/tex]Topic: AP Calculus AB/BC (Calculus I/I + II)
Unit: Derivatives
Book: College Calculus 10e
Divide 30 in the ratio 1 : 4
Answers
Answer:
6 : 24
Step-by-step explanation:
If we are in the ratio of 1 to 4, the total is 1+4 = 5
Divide 30 by 5
30/5 = 6
Multiply each term in the ratio by 6
1 :4
1*6 : 4*6
6 : 24
Answer:
total ratio:
[tex] = 1 + 4 \\ = 5[/tex]
For the portion of 1:
[tex] = 30 \div \frac{1}{5} \\ = 30 \times 5 \\ = 150[/tex]
For the portion of 4:
[tex] = 30 \div \frac{4}{5} \\ = 30 \times \frac{5}{4} \\ = 37.5[/tex]
= 30 : 7.5
An airplane flies 105 miles in ½ hour. How far can it fly in 1 ¼ hours at the same rate of speed?
Answers
Answer:
262.5 miles
Step-by-step explanation:
Correct me if I am wrong
A line that passes through the origin also passes through the point (6,2). What is the slope of the line?
please answer with an explanation
Answers
9514 1404 393
Answer:
1/3
Step-by-step explanation:
The slope of a line is the ratio of its "rise" to its "run." The "rise" is the change in vertical distance, and the "run" is the corresponding change in horizontal distance between two points on the line. The formula for the slope is ...
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}\qquad\text{where $(x_1,y_1)$ and $(x_2,y_2)$ are points on the line}[/tex]
In this problem, you are told the line passes through the origin, which is point (x, y) = (0, 0), and through point (6, 2). Using these coordinates in the slope formula gives ...
[tex]m=\dfrac{2-0}{6-0}=\dfrac{2}{6}=\boxed{\dfrac{1}{3}}[/tex]
__
You may notice that when the line passes through the origin, the slope is simply the ratio y/x of any point on the line. Here, that ratio is 2/6 = 1/3.
_____
Additional comment
A line through the origin is the graph of a proportional relationship. That is, y is proportional to x. The slope of the line is the constant of proportionality. The equation of the line is ...
y = kx . . . . . . where k is the constant of proportionality.
The line in this problem statement will have the equation ...
y = (1/3)x
HELPPPPPPP PLEASEEEEEEE
Answers
Answer:
150 dollars. if I am wrong correct me
Answer:
C and D
Step-by-step explanation:
15 to 30 galons at $9.95 to $21.00
the minimum amount can be found by calculating the minimum amount sold at a minimum price 15*9.95 = $149.25
the maximum amount can be found by calculating the maximum amount sold at a maximum price 30*21 = $630
there are 2 choices that are between 149.25 and 630, C, and D
I’m struggling with this question someone help ASAP plz
Answers
Answer:
The correct answer is:
30 = 10 + 3(h - 2)30 = 10 + 3h - 6
26 = 3h
h = 8.67
Step-by-step explanation:
We're gonna calculate by our part the hours a new costumer can rent a bike and pay a total of $30, using the original function:
f (h) = 10 + 3(h - 2)Where:
f (h) = Total cost. h = the number of hours.We know The total money spent must be $30, by this reason, the function change to:
30 = 10 + 3(h - 2)Now, we must clear the h variable, by this reason, we multiply 3 by h and 2:
30 = 10 + 3*h - 3*2 30 = 10 + 3h - 6We pass the 10 and the -6 to the left side of the equality:
30 - 10 + 6 = 3h (Remember to change the signs when you do this step) 26 = 3hFinally, we pass the 3 to the left side of the equality:
26 / 3 = h (the 3 pass to divide because is multiplying the x)
8.666666666667 = hIf we just use two decimals, the number of hours is:
h = 8.67How the third option is the one that shows this calculation and result, that is the correct answer.
Given: triangle ABC with side lengths a, b, and c, and height h
Prove: Area = 1/2absin C
Answers
Answer:
Step-by-step explanation:
Statements Reasons
1). ΔABC with side lengths a, b, c, and h 1). Given
2). Area = [tex]\frac{1}{2}bh[/tex] 2). Triangle area formula
3). [tex]\text{sin}C=\frac{h}{a}[/tex] 3). Definition of sine
4). asin(C) = h 4). Multiplication property of
equality.
5). Area = [tex]\frac{1}{2}ba\text{sin}C[/tex] 5). Substitution property
6). Area = [tex]\frac{1}{2}ab\text{sin}C[/tex] 6). Commutative property of
multiplication.
Hence, proved.
Detroit's population in 2012 was 699,710 people. Detroit's population in 2016 was 678,045 people.
What is the absolute change from 2012 to 2016?
Round your answer to the nearest person.
Answers
Answer:
The absolute change was of -21,665 people.
Step-by-step explanation:
Absolute change:
Final value subtracted by the initial value.
In this question:
Initial value: 699,710
Final value: 678,045
What is the absolute change from 2012 to 2016?
678045 - 699710 = -21,665
The absolute change was of -21,665 people.
Find dy/dx of the function y = √x sec*-1 (√x)
Answers
Hi there!
[tex]\large\boxed{\frac{dy}{dx} = \frac{1}{2\sqrt{x}}sec^{-1}(\sqrt{x}) + \frac{1}{2|\sqrt{x}|\sqrt{{x} - 1}}}[/tex]
[tex]y = \sqrt{x} * sec^{-1}(-\sqrt{x}})[/tex]
Use the chain rule and multiplication rules to solve:
g(x) * f(x) = f'(x)g(x) + g'(x)f(x)
g(f(x)) = g'(f(x)) * 'f(x))
Thus:
f(x) = √x
g(x) = sec⁻¹ (√x)
[tex]\frac{dy}{dx} = \frac{1}{2\sqrt{x}}sec^{-1}(\sqrt{x}) + \sqrt{x} * \frac{1}{\sqrt{x}\sqrt{\sqrt{x}^{2} - 1}} * \frac{1}{2\sqrt{x}}[/tex]
Simplify:
[tex]\frac{dy}{dx} = \frac{1}{2\sqrt{x}}sec^{-1}(\sqrt{x}) + \sqrt{x} * \frac{1}{2|x|\sqrt{{x} - 1}}[/tex]
[tex]\frac{dy}{dx} = \frac{1}{2\sqrt{x}}sec^{-1}(\sqrt{x}) + \frac{1}{2|\sqrt{x}|\sqrt{{x} - 1}}[/tex]
Answer:
[tex]\displaystyle y' = \frac{arcsec(\sqrt{x})}{2\sqrt{x}} + \frac{1}{2|\sqrt{x}|\sqrt{x - 1}}[/tex]
General Formulas and Concepts:
Algebra I
Exponential Rule [Rewrite]: [tex]\displaystyle b^{-m} = \frac{1}{b^m}[/tex]Exponential Rule [Root Rewrite]: [tex]\displaystyle \sqrt[n]{x} = x^{\frac{1}{n}}[/tex]Calculus
Derivatives
Derivative Notation
Basic Power Rule:
f(x) = cxⁿf’(x) = c·nxⁿ⁻¹Derivative Rule [Product Rule]: [tex]\displaystyle \frac{d}{dx} [f(x)g(x)]=f'(x)g(x) + g'(x)f(x)[/tex]
Derivative Rule [Chain Rule]: [tex]\displaystyle \frac{d}{dx}[f(g(x))] =f'(g(x)) \cdot g'(x)[/tex]
Arctrig Derivative: [tex]\displaystyle \frac{d}{dx}[arcsec(u)] = \frac{u'}{|u|\sqrt{u^2 - 1}}[/tex]
Step-by-step explanation:
Step 1: Define
Identify
[tex]\displaystyle y = \sqrt{x}sec^{-1}(\sqrt{x})[/tex]
Step 2: Differentiate
Rewrite: [tex]\displaystyle y = \sqrt{x}arcsec(\sqrt{x})[/tex]Product Rule: [tex]\displaystyle y' = \frac{d}{dx}[\sqrt{x}]arcsec(\sqrt{x}) + \sqrt{x}\frac{d}{dx}[arcsec(\sqrt{x})][/tex]Chain Rule: [tex]\displaystyle y' = \frac{d}{dx}[\sqrt{x}]arcsec(\sqrt{x}) + \bigg[ \sqrt{x}\frac{d}{dx}[arcsec(\sqrt{x})] \cdot \frac{d}{dx}[\sqrt{x}] \bigg][/tex]Rewrite [Exponential Rule - Root Rewrite]: [tex]\displaystyle y' = \frac{d}{dx}[x^\bigg{\frac{1}{2}}]arcsec(\sqrt{x}) + \bigg[ \sqrt{x}\frac{d}{dx}[arcsec(\sqrt{x})] \cdot \frac{d}{dx}[x^\bigg{\frac{1}{2}}] \bigg][/tex]Basic Power Rule: [tex]\displaystyle y' = \frac{1}{2}x^\bigg{\frac{1}{2} - 1}arcsec(\sqrt{x}) + \bigg[ \sqrt{x}\frac{d}{dx}[arcsec(\sqrt{x})] \cdot \frac{1}{2}x^\bigg{\frac{1}{2} - 1} \bigg][/tex]Simplify: [tex]\displaystyle y' = \frac{1}{2}x^\bigg{\frac{-1}{2}}arcsec(\sqrt{x}) + \bigg[ \sqrt{x}\frac{d}{dx}[arcsec(\sqrt{x})] \cdot \frac{1}{2}x^\bigg{\frac{-1}{2}} \bigg][/tex]Rewrite [Exponential Rule - Rewrite]: [tex]\displaystyle y' = \frac{1}{2x^\bigg{\frac{1}{2}}}arcsec(\sqrt{x}) + \bigg[ \sqrt{x}\frac{d}{dx}[arcsec(\sqrt{x})] \cdot \frac{1}{2x^\bigg{\frac{1}{2}}} \bigg][/tex]Rewrite [Exponential Rule - Root Rewrite]: [tex]\displaystyle y' = \frac{1}{2\sqrt{x}}arcsec(\sqrt{x}) + \bigg[ \sqrt{x}\frac{d}{dx}[arcsec(\sqrt{x})] \cdot \frac{1}{2\sqrt{x}} \bigg][/tex]Arctrig Derivative: [tex]\displaystyle y' = \frac{1}{2\sqrt{x}}arcsec(\sqrt{x}) + \bigg[ \sqrt{x}\frac{1}{|\sqrt{x}|\sqrt{(\sqrt{x})^2 - 1}} \cdot \frac{1}{2\sqrt{x}} \bigg][/tex]Simplify: [tex]\displaystyle y' = \frac{arcsec(\sqrt{x})}{2\sqrt{x}} + \frac{1}{2|\sqrt{x}|\sqrt{x - 1}}[/tex]Topic: AP Calculus AB/BC (Calculus I/I + II)
Unit: Derivatives
Book: College Calculus 10e
At a sale this week, a sofa is being sold for $117.60. This is a 72% discount from the original price. What is the original price?
Answers
In which quadrant do the points have negative x-coordinates and negative y-coordinates?
Answers
Hi there!
»»————- ★ ————-««
I believe your answer is:
Quadrant III
»»————- ★ ————-««
Here’s why:
⸻⸻⸻⸻
The plane is split into four quadrants. Quadrant III houses all the points with negative signs for both X and Y values.⸻⸻⸻⸻
See the attached picture for reference.
⸻⸻⸻⸻
»»————- ★ ————-««
Hope this helps you. I apologize if it’s incorrect.
Which problem has a greater (bigger) answer? Solve both, choose the one that has the bigger answer and explain (1-2 sentences) how you found your
answer.
1) (2 + 3) (5 + 5)
2)2 + 3 x 5 + 5 =
Answers
= 10 + 15 + 10 + 15 =
= 50
2) 5 • 10 =
= 50
I WILL GIVE BRAINLIEST FAST
Answers
Answer:
is opposite line BC. Answer is letter E.
Find the measure of of RA.
Answers
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
g(x)=(cosθsinθ)^4 what's the differential
Answers
Answer:
sin²2θ. (cos θ sin θ). cos 2θ
Step-by-step explanation:
finding g'(x)
g'(x)
(x^n)' = nx^(n -1)= 4 (cosθsinθ)³ . { cosθ. (sinθ)' + sinθ. (cosθ)' }
(cosθ)' = - sinθ (sinθ)' = cosθ= 4 (cosθsinθ)³ { cosθ. cos θ + sinθ.(-sin θ)}
= 4 (cosθsinθ)³{ cos²θ - sin²θ}
cos²θ - sin²θ = cos 2θ2sinθ cosθ = sin 2θ= (4 cosθ sinθ)². (cosθ sinθ). { cos²θ - sin²θ}
= sin²2θ. (cos θ sin θ). cos 2θ
A box has length 4 feet, width 5 feet, and height 8 inches. Find the volume of the box in cubic feet and in cubic inches.
Answers
Answer:
13.4 cubic feet and 23040 inches
Step-by-step explanation:
Answer:
In cubic feet = 13.3 ft^3 ...........or 13.33ft^3
In cubic inches = 23040in^3
Step-by-step explanation:
In cubic feet it becomes
4(5) = 20 feet ^2 ................but we need volume in feet
so 8 inches = .............2/3 of a foot = 0.666667
Answer therefore is (4) x (5) x (0.666667) = 13.32ft^3
In cubic inches it becomes
4 x 12 = 48 inches
5 x 12 = 60 inches
and 8 inches
48 x 60 x 8 = 23040 in^3
We check by squaring the divider
23040/12^3 = 13.333
We only square and square again to find a cube but to square once we do this with area too.
Area 1. = 4 x 5 = 20 feet^2
Area 2. = 48 x 60 = 2880 in ^2 / 12^2 = 20
Given n(A) = 1300, n(A U B) = 2290, and n(A n B) = 360, find n(B).
Answers
Answer:
n(B) = 1350
Step-by-step explanation:
Using Venn sets, we have that:
[tex]n(A \cup B) = n(A) + n(B) - n(A \cap B)[/tex]
Three values are given in the exercise.
The other is n(B), which we have to find. So
[tex]n(A \cup B) = n(A) + n(B) - n(A \cap B)[/tex]
[tex]2290 = 1300 + n(B) - 360[/tex]
[tex]940 + n(B) = 2290[/tex]
[tex]n(B) = 2290 - 940 = 1350[/tex]
So
n(B) = 1350
help me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me me
Answers
Volume of the 3d composite figure is,
(7×6×5)+(7×6×5)/3
= 210+70
= 280 cm³
Relationship between the two volumes,
Volume of the rectangular prism is 3 times the volume of the pyramid.
Answered by GAUTHMATH
Answer:
I was gonna anwer it but somone already did.
Step-by-step explanation:
What is the surface area of the rectangular prism pictured below?
3 meters
9 meters
4 meters
Answers
Answer:
108 meters with the formula lxhxw
Which is equivalent to (-m)4x n2 ?
Answers
Answer:
a.) m⁴n²
Step-by-step explanation:
( -m)⁴ × n ²
A negative base raised to an even powers equals a positive.
m ⁴ × n²
multiply the terms
m⁴n²
Answer:
a.) m⁴n²
Step-by-step explanation:
yea
The CPA Practice Advisor reports that the mean preparation fee for 2017 federal income tax returns was $273. Use this price as the population mean and assume the population standard deviation of preparation fees is $100.A) What is the probability that the mean price for a sample of 30 federal income tax returns is within $16 of the population mean?B) What is the probability that the mean price for a sample of 50 federal income tax returns is within $16 of the population mean?C) What is the probability that the mean price for a sample of 100 federal income tax returns is within $16 of the population mean?D) Which, if any of the sample sizes in part (a), (b), and (c) would you recommend to ensure at least a .95 probability that the same mean is withing $16 of the population mean?
Answers
Answer:
a) 0.6212 = 62.12% probability that the mean price for a sample of 30 federal income tax returns is within $16 of the population mean.
b) 0.7416 = 74.16% probability that the mean price for a sample of 50 federal income tax returns is within $16 of the population mean.
c) 0.8804 = 88.04% probability that the mean price for a sample of 100 federal income tax returns is within $16 of the population mean.
d) None of them ensure, that one which comes closer is a sample size of 100 in option c), to guarantee, we need to keep increasing the sample size.
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.
The CPA Practice Advisor reports that the mean preparation fee for 2017 federal income tax returns was $273. Use this price as the population mean and assume the population standard deviation of preparation fees is $100.
This means that [tex]\mu = 273, \sigma = 100[/tex]
A) What is the probability that the mean price for a sample of 30 federal income tax returns is within $16 of the population mean?
Sample of 30 means that [tex]n = 30, s = \frac{100}{\sqrt{30}}[/tex]
The probability is the p-value of Z when X = 273 + 16 = 289 subtracted by the p-value of Z when X = 273 - 16 = 257. So
X = 289
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{289 - 273}{\frac{100}{\sqrt{30}}}[/tex]
[tex]Z = 0.88[/tex]
[tex]Z = 0.88[/tex] has a p-value of 0.8106
X = 257
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{257 - 273}{\frac{100}{\sqrt{30}}}[/tex]
[tex]Z = -0.88[/tex]
[tex]Z = -0.88[/tex] has a p-value of 0.1894
0.8106 - 0.1894 = 0.6212
0.6212 = 62.12% probability that the mean price for a sample of 30 federal income tax returns is within $16 of the population mean.
B) What is the probability that the mean price for a sample of 50 federal income tax returns is within $16 of the population mean?
Sample of 30 means that [tex]n = 50, s = \frac{100}{\sqrt{50}}[/tex]
X = 289
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{289 - 273}{\frac{100}{\sqrt{50}}}[/tex]
[tex]Z = 1.13[/tex]
[tex]Z = 1.13[/tex] has a p-value of 0.8708
X = 257
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{257 - 273}{\frac{100}{\sqrt{50}}}[/tex]
[tex]Z = -1.13[/tex]
[tex]Z = -1.13[/tex] has a p-value of 0.1292
0.8708 - 0.1292 = 0.7416
0.7416 = 74.16% probability that the mean price for a sample of 50 federal income tax returns is within $16 of the population mean.
C) What is the probability that the mean price for a sample of 100 federal income tax returns is within $16 of the population mean?
Sample of 30 means that [tex]n = 100, s = \frac{100}{\sqrt{100}}[/tex]
X = 289
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{289 - 273}{\frac{100}{\sqrt{100}}}[/tex]
[tex]Z = 1.6[/tex]
[tex]Z = 1.6[/tex] has a p-value of 0.9452
X = 257
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{257 - 273}{\frac{100}{\sqrt{100}}}[/tex]
[tex]Z = -1.6[/tex]
[tex]Z = -1.6[/tex] has a p-value of 0.0648
0.9452 - 0.0648 =
0.8804 = 88.04% probability that the mean price for a sample of 100 federal income tax returns is within $16 of the population mean.
D) Which, if any of the sample sizes in part (a), (b), and (c) would you recommend to ensure at least a .95 probability that the same mean is withing $16 of the population mean?
None of them ensure, that one which comes closer is a sample size of 100 in option c), to guarantee, we need to keep increasing the sample size.
C is actually 0.8904
for anybody else stuck on this wondering why cengage is telling you c is wrong
Calculate the pH of a buffer solution made by mixing 300 mL of 0.2 M acetic acid, CH3COOH, and 200 mL of 0.3 M of its salt sodium acetate, CH3COONa, to make 500 mL of solution. Ka for CH3COOH = 1.76×10–5
Answers
Answer:
Approximately [tex]4.75[/tex].
Step-by-step explanation:
Remark: this approach make use of the fact that in the original solution, the concentration of [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] are equal.
[tex]{\rm CH_3COOH} \rightleftharpoons {\rm CH_3COO^{-}} + {\rm H^{+}}[/tex]
Since [tex]\rm CH_3COONa[/tex] is a salt soluble in water. Once in water, it would readily ionize to give [tex]\rm CH_3COO^{-}[/tex] and [tex]\rm Na^{+}[/tex] ions.
Assume that the [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] ions in this solution did not disintegrate at all. The solution would contain:
[tex]0.3\; \rm L \times 0.2\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COOH[/tex], and
[tex]0.06\; \rm mol[/tex] of [tex]\rm CH_3COO^{-}[/tex] from [tex]0.2\; \rm L \times 0.3\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COONa[/tex].
Accordingly, the concentration of [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] would be:
[tex]\begin{aligned} & c({\rm CH_3COOH}) \\ &= \frac{n({\rm CH_3COOH})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].
[tex]\begin{aligned} & c({\rm CH_3COO^{-}}) \\ &= \frac{n({\rm CH_3COO^{-}})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].
In other words, in this buffer solution, the initial concentration of the weak acid [tex]\rm CH_3COOH[/tex] is the same as that of its conjugate base, [tex]\rm CH_3COO^{-}[/tex].
Hence, once in equilibrium, the [tex]\rm pH[/tex] of this buffer solution would be the same as the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex].
Calculate the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex] from its [tex]{\rm K}_{a}[/tex]:
[tex]\begin{aligned} & {\rm pH}(\text{solution}) \\ &= {\rm pK}_{a} \\ &= -\log_{10}({\rm K}_{a}) \\ &= -\log_{10} (1.76 \times 10^{-5}) \\ &\approx 4.75\end{aligned}[/tex].
Can you please help me with this question
Answers
Assume that the breaking system of a train consists of two components connected in series with both of them following Weibull distributions. For the first component the shape parameter is 2.1 and the characteristic life is 100,000 breaking events. For the second component the shape parameter is 1.8 and characteristic life of 80,000. Find the reliability of the system after 2,000 breaking events:
Answers
Answer:
0.9984
Step-by-step explanation:
we have shape parameter for the first component as 2.1
characteristics life = 100000
for this component
we have
exp(-2000/100000)².¹
= e^-0.0002705
= 0.9997
for the second component
shape parameter = 1.8
characteristic life = 80000
= exp(-2000/80000)¹.⁸
= e^-0.001307
= 0.9987
the reliability oif the system after 2000 events
= 0.9987 * 0.9997
= 0.9984
Mischa wrote the quadratic equation 0=_x2+4x-7 in standard form. If a = -1, what is the value of c in her equation?
C=-7
C= 1
c=4
c=7
Answers
Answer:
A. c = -7
Step-by-step explanation:
Standard form of a quadratic equation is given as ax² + bx + c = 0, where,
a, b, and c are known values not equal to 0,
x is the variable.
Given a quadratic equation of -x² + 4x - 7, therefore,
a = -1
b = 4
c = -7
What sum is represented by the following number line?
Answers
Answer:
[tex]2\frac{3}{4} +(-4\frac{1}{4} )=-1\frac{2}{4}[/tex]
Step-by-step explanation:
That's the only equation that makes sense to the number line
4ab-3a+3bx-2ab anyone know the answer to this problem?
Answers
Answer:
-3a+3bx+2ab
Step-by-step explanation:
A wiper blade of a car is of length 24 cm sweeping through an angle of begin mathsize 18px style text 120° end text end style. The total area cleaned at one sweep of the blade is
Answers
Answer:
[tex]A=603.18\ cm^2[/tex]
Step-by-step explanation:
The length of a blade, r = 24 cm
The sweeping angle is 120°.
We need to find the total area cleaned at one sweep of the blade. The area of sector is given by :
[tex]A=\dfrac{\theta}{360}\times \pi r^2[/tex]
[tex]A=\dfrac{120}{360}\times \pi \times 24^2\\\\=603.18\ cm^2[/tex]
So, the total area cleaned at one sweep of the blade is [tex]603.18\ cm^2[/tex].