Answer:
B.
Step-by-step explanation:
First, notice that we can cancel out an x in the second term. Thus:
[tex]\displaystyle \frac{3x^2}{x^2+x} =\frac{3x^2}{x(x+1)} =\frac{3x}{x+1}[/tex]
As with the last question, change the sign to multiplication and "flip" the second term:
[tex]\displaystyle \frac{2x-1}{x+1}\cdot \frac{x+1}{3x}[/tex]
Multiply straight across:
[tex]\displaystyle =\frac{(2x-1)(x+1)}{(x+1)(3x)}[/tex]
We can cancel the (x + 1) term:
[tex]\displaystyle =\frac{2x-1}{3x}[/tex]
This cannot be simplified further. Hence, our answer is B.
Answer:
It is B)
Step-by-step explanation:
Ap3x Approved
If the ratio of red hairbands to green hair bands is 5 to 9 with a total of 70 hairbands, how many of them are green?
Answer:
45
Step-by-step explanation:
This can be written as 5r:9g. Add 5 and 9 to get the total of 14. You can write a ratio of 9 green: (out of) 14 total = x green: (out of) 70 total. Multiply 9 and 14 by 7 to get 45:70. Therefore, if there are 70 hairbands, 45 are green.
Over the past several years, the proportion of one-person households has been increasing. The Census Bureau would like to test the hypothesis that the proportion of one-person households exceeds 0.27. A random sample of 125 households found that 43 consisted of one person. The Census Bureau would like to set α = 0.05. Use the critical value approach to test this hypothesis. Explain.
Answer:
For this case we can find the critical value with the significance level [tex]\alpha=0.05[/tex] and if we find in the right tail of the z distribution we got:
[tex] z_{\alpha}= 1.64[/tex]
The statistic is given by:
[tex]z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}[/tex] (1)
Replacing we got:
[tex]z=\frac{0.344 -0.27}{\sqrt{\frac{0.27(1-0.27)}{125}}}=1.86[/tex]
Since the calculated value is higher than the critical value we have enough evidence to reject the null hypothesis and we can conclude that the true proportion of households with one person is significantly higher than 0.27
Step-by-step explanation:
We have the following dataset given:
[tex] X= 43[/tex] represent the households consisted of one person
[tex]n= 125[/tex] represent the sample size
[tex] \hat p= \frac{43}{125}= 0.344[/tex] estimated proportion of households consisted of one person
We want to test the following hypothesis:
Null hypothesis: [tex]p \leq 0.27[/tex]
Alternative hypothesis: [tex]p>0.27[/tex]
And for this case we can find the critical value with the significance level [tex]\alpha=0.05[/tex] and if we find in the right tail of the z distribution we got:
[tex] z_{\alpha}= 1.64[/tex]
The statistic is given by:
[tex]z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}[/tex] (1)
Replacing we got:
[tex]z=\frac{0.344 -0.27}{\sqrt{\frac{0.27(1-0.27)}{125}}}=1.86[/tex]
Since the calculated value is higher than the critical value we have enough evidence to reject the null hypothesis and we can conclude that the true proportion of households with one person is significantly higher than 0.27
On a piece of paper, graph y + 2 ≤ -2/3x +4. Then determine which answer choice matches the graph you drew.
Answer:
B
Step-by-step explanation:
You only need to look at the comparison symbol (≤) to determine the correct graph. It tells you the shading is below the boundary line, and the boundary line is included in the solution region (a solid line).
The shading is below the line because y-values are less than (or equal to) values on the line.
Choice B matches the attached graph.
Answer:
it is graph b
Step-by-step explanation:
College students were given three choices of pizza toppings and asked to choose one favorite Results are shown in the table toppings Sremam 15 24 28 28 15 1 11 23 28 cheese meat 23 15 veggie Estimate the probability that a randomly selected student who is a junior or senior prefers veggie. Round the answer to the nearest thousandth
A. 371
B. 220
C. 395
D. 662
Answer:
B. 0.220
Step-by-step explanation:
The table is presented properly below:
[tex]\left|\begin{array}{c|cccc|c}$toppings&$Freshman&$Sophomore&$Junior&$Senior&$Total\\---&---&---&---&---&---\\$Cheese&11&15&24&28&78\\$Meat&23&28&15&11&77\\$Veggie&15&11&23&28&77\\---&---&---&---&---&---\\$Total&&&&&232\end{array}\right|[/tex]
Number of junior students who prefers veggies =23
Number of senior students who prefers veggies =28
Total =23+28=51
Therefore, the probability that a randomly selected student who is a junior or senior prefers veggie
=51/232
=0.220 (to the nearest thousandth)
The correct option is B.
x=-4
Tell whether it’s graph is a horizontal or a vertical line
Answer:
Vertical Line
Step-by-step explanation:
A vertical line is x = [a number]
A horizontal line is y = [a number]
Answer:
vertical line
Step-by-step explanation:
A vertical line is of the form
x =
All the x values are the same and the y value changes
x = -4 is a vertical line
A sphere and a cylinder have the same radius and height. The volume of the cylinder is 30 meters cubed A sphere with height h and radius r. A cylinder with height h and radius r. What is the volume of the sphere? 10 meters cubed 20 meters cubed 30 meters cubed 40 meters cubed
Answer:
30 m^3
Step-by-step explanation:
Answer:
B. 20m3
Step-by-step explanation:
i dont know if its correct, hope it is tho
If f(x) = 4x – 8 and g(x) = 5x + 6, find (f - g)(x).
Answer:
(f - g)(x) = -x - 14
Step-by-step explanation:
Step 1: Plug in equations
4x - 8 - (5x + 6)
Step 2; Distribute negative
4x - 8 - 5x - 6
Step 3: Combine like terms
-x - 14
Answer:
-x-14
Step-by-step explanation:
Hope this helps
3. A tunnel is 300 feet deep and makes an angle of 30° with the ground, as shown below.
30°
300 feet
Tunne
How long is the tunnel?
Answer:
173.20 ft
Step-by-step explanation:
[tex] \tan \: 30 \degree = \frac{length \: of \: tunnel}{depth \: of \: tunnel} \\ \\ \frac{1}{ \sqrt{3} } = \frac{length \: of \: tunnel}{300} \\ \\ length \: of \: tunnel \\ \\ = \frac{300}{ \sqrt{3} } \\ \\ = \frac{300 \sqrt{3} }{3} \\ \\ = 100 \sqrt{3} \\ \\ = 100 \times 1.7320 \\ \\ = 173.20 \: ft[/tex]
. If α and β are the roots of
2x^2+7x-9=0 then find the equation whose roots are
α/β ,β/α
Answer:
[tex]18x^2+85x+18 = 0[/tex]
Step-by-step explanation:
Given Equation is
=> [tex]2x^2+7x-9=0[/tex]
Comparing it with [tex]ax^2+bx+c = 0[/tex], we get
=> a = 2, b = 7 and c = -9
So,
Sum of roots = α+β = [tex]-\frac{b}{a}[/tex]
α+β = -7/2
Product of roots = αβ = c/a
αβ = -9/2
Now, Finding the equation whose roots are:
α/β ,β/α
Sum of Roots = [tex]\frac{\alpha }{\beta } + \frac{\beta }{\alpha }[/tex]
Sum of Roots = [tex]\frac{\alpha^2+\beta^2 }{\alpha \beta }[/tex]
Sum of Roots = [tex]\frac{(\alpha+\beta )^2-2\alpha\beta }{\alpha\beta }[/tex]
Sum of roots = [tex](\frac{-7}{2} )^2-2(\frac{-9}{2} ) / \frac{-9}{2}[/tex]
Sum of roots = [tex]\frac{49}{4} + 9 /\frac{-9}{2}[/tex]
Sum of Roots = [tex]\frac{49+36}{4} / \frac{-9}{2}[/tex]
Sum of roots = [tex]\frac{85}{4} * \frac{2}{-9}[/tex]
Sum of roots = S = [tex]-\frac{85}{18}[/tex]
Product of Roots = [tex]\frac{\alpha }{\beta } \frac{\beta }{\alpha }[/tex]
Product of Roots = P = 1
The Quadratic Equation is:
=> [tex]x^2-Sx+P = 0[/tex]
=> [tex]x^2 - (-\frac{85}{18} )x+1 = 0[/tex]
=> [tex]x^2 + \frac{85}{18}x + 1 = 0[/tex]
=> [tex]18x^2+85x+18 = 0[/tex]
This is the required quadratic equation.
Answer:
α/β= -2/9 β/α=-4.5
Step-by-step explanation:
So we have quadratic equation 2x^2+7x-9=0
Lets fin the roots using the equation's discriminant:
D=b^2-4*a*c
a=2 (coef at x^2) b=7(coef at x) c=-9
D= 49+4*2*9=121
sqrt(D)=11
So x1= (-b+sqrt(D))/(2*a)
x1=(-7+11)/4=1 so α=1
x2=(-7-11)/4=-4.5 so β=-4.5
=>α/β= -2/9 => β/α=-4.5
An inverse variation includes the point (-8,-19). Which point would also belong in this inverse variation? A. (-19,-8) B. (-8,19) C. (-19,8) D. (8,-19)
Answer:
(A) (-19,-8)
Step-by-step explanation:
Given that the graph is an inverse variation.
The equation of variation is:
[tex]x=\dfrac{k}{y}[/tex]
Since point (-8, -19) is on the graph
[tex]-8=\dfrac{k}{-19}\\k=152[/tex]
Therefore, the equation connecting x and y is:
[tex]x=\dfrac{152}{y}[/tex]
[tex]\text{When y=-8},x=\dfrac{152}{-8}=-19\\\\\text{When y=19},x=\dfrac{152}{19}=8\\\\\text{When y=8},x=\dfrac{152}{8}=19\\\\\text{When y=-19},x=\dfrac{152}{-19}=-8[/tex]
Therefore, the point that is also on the graph is:
(A) (-19,-8)
Can somebody help me i have to drag the functions on top onto the bottom ones to match their inverse functions.
Answer:
1. x/5
2. cubed root of 2x
3.x-10
4.(2x/3)-17
Step-by-step explanation:
Answer:
Step-by-step explanation:
1. Lets find the inverse function for function f(x)=2*x/3-17
To do that first express x through f(x):
2*x/3= f(x)+17
2*x=(f(x)+17)*3
x=(f(x)+17)*3/2 done !!! (1)
Next : to get the inverse function from (1) substitute x by f'(x) and f(x) by x.
So the required function is f'(x)=(x+17)*3/2 or f'(x)=3*(x+17)/2
This is function is No4 in our list. So f(x)=2*x/3-17 should be moved to the box No4 ( on the bottom) of the list.
2. Lets find the inverse function for function f(x)=x-10
To do that first express x through f(x):
x= f(x)+10
x=f(x)+10 done !!! (2)
Next : to get the inverse function from (2) substitute x by f'(x) and f(x) by x.
So the required function is f'(x)=x+10
This is function is No3 in our list. So f(x)=x-10 should be moved to the box No3 ( from the top) of the list.
3.Lets find the inverse function for function f(x)=sqrt 3 (2x)
To do that first express x through f(x):
2*x= f(x)^3
x=f(x)^3/2 done !!! (3)
Next : to get the inverse function from (3) substitute x by f'(x) and f(x) by x.
So the required function is f'(x)=x^3/2
This is function No2 in our list. So f(x)=sqrt 3 (2x) should be moved to the box No2 ( from the top) of the list.
4.Lets find the inverse function for function f(x)=x/5
To do that first express x through f(x):
x=f(x)*5 done !!! (4)
Next : to get the inverse function from (4) substitute x by f'(x) and f(x) by x.
So the required function is f'(x)=x*5 or f'(x)=5*x
This is function No1 in our list. So f(x)=x/5 should be moved to the box No1 ( on the top) of the list.
Q4. A simple random sample of size n=180 is obtained from a population whose size=20,000 and whose population proportion with a specified characteristic is p=0.45. Determine whether the sampling distribution has an approximate normal distribution. Show your work that supports your conclusions.
Answer:
np = 81 , nQ = 99
Step-by-step explanation:
Given:
X - B ( n = 180 , P = 0.45 )
Find:
Sampling distribution has an approximate normal distribution
Computation:
nP & nQ ≥ 5
np = n × p
np = 180 × 0.45
np = 81
nQ = n × (1-p)
nQ = 180 × ( 1 - 0.45 )
nQ = 99
[tex]Therefore, sampling\ distribution\ has\ an\ approximately\ normal\ distribution.[/tex]
Find the directional derivative of at the point (1, 3) in the direction toward the point (3, 1). g
Complete Question:
Find the directional derivative of g(x,y) = [tex]x^2y^5[/tex]at the point (1, 3) in the direction toward the point (3, 1)
Answer:
Directional derivative at point (1,3), [tex]D_ug(1,3) = \frac{162}{\sqrt{8} }[/tex]
Step-by-step explanation:
Get [tex]g'_x[/tex] and [tex]g'_y[/tex] at the point (1, 3)
g(x,y) = [tex]x^2y^5[/tex]
[tex]g'_x = 2xy^5\\g'_x|(1,3)= 2*1*3^5\\g'_x|(1,3) = 486[/tex]
[tex]g'_y = 5x^2y^4\\g'_y|(1,3)= 5*1^2* 3^4\\g'_y|(1,3)= 405[/tex]
Let P = (1, 3) and Q = (3, 1)
Find the unit vector of PQ,
[tex]u = \frac{\bar{PQ}}{|\bar{PQ}|} \\\bar{PQ} = (3-1, 1-3) = (2, -2)\\{|\bar{PQ}| = \sqrt{2^2 + (-2)^2}\\[/tex]
[tex]|\bar{PQ}| = \sqrt{8}[/tex]
The unit vector is therefore:
[tex]u = \frac{(2, -2)}{\sqrt{8} } \\u_1 = \frac{2}{\sqrt{8} } \\u_2 = \frac{-2}{\sqrt{8} }[/tex]
The directional derivative of g is given by the equation:
[tex]D_ug(1,3) = g'_x(1,3)u_1 + g'_y(1,3)u_2\\D_ug(1,3) = (486*\frac{2}{\sqrt{8} } ) + (405*\frac{-2}{\sqrt{8} } )\\D_ug(1,3) = (\frac{972}{\sqrt{8} } ) + (\frac{-810}{\sqrt{8} } )\\D_ug(1,3) = \frac{162}{\sqrt{8} }[/tex]
What is the equation of a line passes thru the point (4, 2) and is perpendicular to the line whose equation is y = ×/3 - 1 ??
Answer:
Perpendicular lines have slopes that are opposite and reciprocal. Therefore, the line we are looking for has a -3 slope.
y= -3x+b
Now, we can substitute in the point given to find the intercept.
2= -3(4)+b
2= -12+b
b=14
Finally, put in everything we've found to finish the equation.
y= -3x+14
Answer:
y = -3x + 14
Step-by-step explanation:
First find the reciprocal slope since it is perpendicular. Slope of the other line is 1/3 so the slope for our new equation is -3.
Plug information into point-slope equation
(y - y1) = m (x-x1)
y - 2 = -3 (x-4)
Simplify if needed
y - 2 = -3x + 12
y = -3x + 14
Simplify the algebraic expression: 7x2 + 6x – 9x – 6x2 + 15. A) x2 + 15x + 15 B) x2 – 3x + 15 C) 13x2 + 3x + 15 D) x4 – 3x + 15
Answer:
B) [tex]x^2-3x+15[/tex]
Step-by-step explanation:
[tex]7x^2+6x-9x-6x^2+15=\\7x^2-6x^2+6x-9x+15=\\x^2+6x-9x+15=\\x^2-3x+15[/tex]
A) [tex]x^2+15x+15[/tex]
B) [tex]x^2-3x+15[/tex]
C) [tex]13x^2 + 3x + 15[/tex]
D) [tex]x^4-3x + 15[/tex]
━━━━━━━☆☆━━━━━━━
▹ Answer
B. x² - 3x + 15
▹ Step-by-Step Explanation
7x² + 6x - 9x - 6x² + 15
Collect like terms
x² + 6x - 9x + 15
Subtract
x² - 3x + 15
Final Answer
x² - 3x + 15
Hope this helps!
- CloutAnswers ❁
Brainliest is greatly appreciated!
━━━━━━━☆☆━━━━━━━
what happens to the value of the expression n+15n as n decreases? answer
Answer:
The value will decrease.
Step-by-step explanation:
2-x=-3(x+4)+6 please help
Answer:
2-x=-3x-12+6
2-x=-3x-6
8=-3x+x
8=-2x
x=-4
hope it's clear
mark me as brainliest
Answer:
X = -4Option B is the correct option.
Step by step explanation
2 - x = -3 ( x + 4) +6
Distribute -3 through the paranthesis
2 - x = - 3x - 12 + 6
Calculate
2 - x = - 3x - 6
Move variable to LHS and change its sign
2 - x + 3x = -6
Move constant to R.H.S and change its sign
- x + 3x = -6 - 2
Collect like terms and simplify
2x = -8
Divide both side by 2
2x/2 = -8/2
Calculate
X = -4
Hope this helps....
Good luck on your assignment..
If the area of a circular cookie is 28.26 square inches, what is the APPROXIMATE circumference of the cookie? Use 3.14 for π.
75.2 in.
56.4 in.
37.6 in.
18.8 in.
Answer:
Step-by-step explanation:
c= 2(pi)r
Area = (pi)r^2
28.26 = (pi) r^2
r =[tex]\sqrt{9}[/tex] = 3
circumference = 2 (3.14) (3)
= 18.8 in
Answer: approx 18.8 in
Step-by-step explanation:
The area of the circle is
S=π*R² (1) and the circumference of the circle is C= 2*π*R (2)
So using (1) R²=S/π=28.26/3.14=9
=> R= sqrt(9)
R=3 in
So using (2) calculate C=2*3.14*3=18.84 in or approx 18.8 in
find the lateral surface area of a cylinder whose radius is 1.2 mm and whose height is 2 mm
Answer:
Lateral Surface Area = 15.072 [tex]mm^2[/tex]
Step-by-step explanation:
Given that:
Base of Cylinder has radius, r = 1.2 mm
Height, h = 2 mm
To find:
Lateral Surface area of cylinder = ?
Solution:
We know that total surface area of a cylinder is given by:
[tex]TSA = 2\pi r^2+2\pi rh[/tex]
Here [tex]2\pi r^2[/tex] is the area of two circular bases of the cylinder and
[tex]2\pi rh[/tex] is the lateral surface area.
Please refer to the attached image for a better understanding of the Lateral and Total Surface Area.
So, LSA = [tex]2\pi rh[/tex]
[tex]\Rightarrow LSA = 2 \times 3.14 \times 1.2 \times 2\\\Rightarrow LSA = 6.28 \times 2.4\\\Rightarrow LSA = 15.072\ mm^2[/tex]
So, the answer is:
Lateral Surface Area of given cylinder = 15.072 [tex]mm^2[/tex]
Answer:
LSA = 24.1
Step-by-step explanation:
I just did this, I dont know how to upload my work, but It marked it as right and gave me the green check mark. The answer is 24.1
Hi, can someone help me on this. I'm stuck --
Answer:
a) Fx=-5N Fy=-5*sqrt(3) N b) Fx= 5*sqrt(3) N Fy=-5N
c) Fx=-5*sqrt(2) N Fy=-5*sqrt(2) N
Step-by-step explanation:
The arrow's F ( weight) component on axle x is Fx= F*sinA and on axle y is
Fy=F*cosA
a) The x component and y component both are opposite directed to axle x and axle y accordingly. So both components are negative.
So Fx = - 10*sin(30)= -5 N Fy= -10*cos(30)= -10*sqrt(3)/2= -5*sqrt (3) N
b) Now the x component is co directed to axle x , and y component is opposite directed to axle y.
So x component is positive and y components is negative
So Fx = 10*sin(60)= 5*sqrt(3) N Fy= -10*cos(60)= -10*1/2= -5 N
c)The x component and y component both are opposite directed to axle x and axle y accordingly. So both components are negative.
So Fx = - 10*sin(45)= -5*sqrt(2) N
Fy= -10*cos(45)= -10*sqrt(2)/2= -5*sqrt (2) N
Find AC. (Khan Academy-Math)
Answer:
[tex]\boxed{11.78}[/tex]
Step-by-step explanation:
From observations, we can note that BC is the hypotenuse.
As the length of hypotenuse is not given, we can only use tangent as our trig function.
tan(θ) = opposite/adjacent
tan(67) = x/5
5 tan(67) = x
11.77926182 = x
x ≈ 11.78
Find the lateral area of a regular square pyramid if the base edges are of length 12 and the perpendicular height is 8.
Answer:
Lateral area of the pyramid = 120 square units
Step-by-step explanation:
In the figure attached,
A pyramid has been given with square base with edges of 12 units and perpendicular height as 8 units.
Lateral area of a pyramid = Area of the lateral sides
Area of one lateral side = [tex]\frac{1}{2}(\text{Base})(\text{Lateral height})[/tex]
= [tex]\frac{1}{2}(\frac{b}{2})(\sqrt{(\frac{b}{2})^2+h^2})[/tex] [Since l = [tex]\sqrt{r^{2}+h^{2}}[/tex]]
= [tex]\frac{1}{2}(6)(\sqrt{6^2+8^2})[/tex]
= [tex]3\sqrt{100}[/tex]
= 30 units²
Now lateral area of the pyramid = 4 × 30 = 120 square units
Answer: 240 units^2
Step-by-step explanation:
LA= 1/2 Pl
P= perimeter of base
l= lateral height
l= 8^2 + (12/2)^2 = 10^2
P= 12 x 4 = 48
48 x 10 = 480
480/2 = 240
240 units^2
units digit of the number[tex]2^{4000}[/tex]
Answer:
6
Step-by-step explanation:
We want to find the units digit of [tex]2^{4000}[/tex]. Let's first look for a pattern:
[tex]2^{1}=2[/tex]
[tex]2^{2}=4[/tex]
[tex]2^{3}=8[/tex]
[tex]2^{4}=16[/tex]
[tex]2^{5}=32[/tex]
[tex]2^{6}=64[/tex]
[tex]2^{7}=128[/tex]
[tex]2^{8}=256[/tex]
...and so on
Notice the units digits: 2, 4, 8, 6, 2, 4, 8, 6, ... It repeats every four!
This means that for every exponent of 2 that is a multiple of 4 (like 4000 in the problem), the units digit will always be the fourth number in the repeating pattern: 6.
The answer is thus 6.
~ an aesthetics lover
A group of 20 people were asked to remember as many items as possible from a list before and after being taught a memory device. Researchers want to see if there is a significant difference in the amount of items that people are able to remember before and after being taught the memory device. They also want to determine whether or not men and women perform differently on the memory test. They choose α = 0.05 level to test their results. Use the provided data to run a Two-way ANOVA with replication.
A B C
Before After
Male 5 7
4 5
7 8
7 8
7 8
7 8
5 6
7 7
6 7
Female 5 8
5 6
8 8
7 7
6 6
8 9
8 8
6 6
7 6
8 8
Answer:
1. There is no difference in amount of items that people are able to remember before and after being taught the memory device.
2. There is no difference between performance of men and women on memory test.
Step-by-step explanation:
Test 1:
The hypothesis for the two-way ANOVA test can be defined as follows:
H₀: There is no difference in amount of items that people are able to remember before and after being taught the memory device.
Hₐ: There is difference in amount of items that people are able to remember before and after being taught the memory device.
Use MS-Excel to perform the two-way ANOVA text.
Go to > Data > Data Analysis > Anova: Two-way with replication
A dialog box will open.
Input Range: select all data
Rows per sample= 10
Alpha =0.05
Click OK
The ANOVA output is attaches below.
Consider the Columns data:
The p-value is 0.199.
p-value > 0.05
The null hypothesis will not be rejected.
Conclusion:
There is no difference in amount of items that people are able to remember before and after being taught the memory device.
Test 2:
The hypothesis to determine whether or not men and women perform differently on the memory test is as follows:
H₀: There is no difference between performance of men and women on memory test.
Hₐ: There is a difference between performance of men and women on memory test.
Consider the Sample data:
The p-value is 0.075.
p-value > 0.05
The null hypothesis will not be rejected.
Conclusion:
There is no difference between performance of men and women on memory test.
Suppose μ1 and μ2 are true mean stopping distances at 50 mph for cars of a certain type equipped with two different types of braking systems. Use the two-sample t test at significance level 0.01 to test H0: μ1 − μ2 = −10 versus Ha: μ1 − μ2 < −10 for the following data: m = 8, x = 115.6, s1 = 5.04, n = 8, y = 129.3, and s2 = 5.32.
Calculate the test statistic and determine the P-value. (Round your test statistic to two decimal places and your P-value to three decimal places.)
t = ________
P-value = _________
Answer:
Step-by-step explanation:
This is a test of 2 independent groups. Given that μ1 and μ2 are true mean stopping distances at 50 mph for cars of a certain type equipped with two different types of braking systems, the hypothesis are
For null,
H0: μ1 − μ2 = - 10
For alternative,
Ha: μ1 − μ2 < - 10
This is a left tailed test.
Since sample standard deviation is known, we would determine the test statistic by using the t test. The formula is
(x1 - x2)/√(s1²/n1 + s2²/n2)
From the information given,
x1 = 115.6
x2 = 129.3
s1 = 5.04
s2 = 5.32
n1 = 8
n2 = 8
t = (115.6 - 129.3)/√(5.04²/8 + 5.32²/8)
t = - 2.041
Test statistic = - 2.04
The formula for determining the degree of freedom is
df = [s1²/n1 + s2²/n2]²/(1/n1 - 1)(s1²/n1)² + (1/n2 - 1)(s2²/n2)²
df = [5.04²/8 + 5.32²/8]²/[(1/8 - 1)(5.04²/8)² + (1/8 - 1)(5.32²/8)²] = 45.064369/3.22827484
df = 14
We would determine the probability value from the t test calculator. It becomes
p value = 0.030
Since alpha, 0.01 < the p value, 0.03, then we would fail to reject the null hypothesis.
Use the Remainder Theorem to determine which of the roots are roots of F(x). Show your work.
Polynomial: F(x)=x^3-x^2-4x+4
Roots: 1, -2, and 2.
Answer: x1=1 x2=-2 and x3=2
Step-by-step explanation:
1st x1=1 is 1 of the roots , so
F(1)=1-1-4+4=0 - true
So lets divide x^3-x^2-4x+4 by (x-x1), i.e (x^3-x^2-4x+4) /(x-1)=(x^2-4)
x^2-4 can be factorized as (x-2)*(x+2)
So x^3-x^2-4x+4=(x-1)*(x^2-4)=(x-1)(x-2)*(x+2)
So there are 3 dofferent roots:
x1=1 x2=-2 and x3=2
Find the volume of the solid generated by revolving the region enclosed by the triangle with vertices (1 comma 0 ), (3 comma 2 ), and (1 comma 2 )about the y-axis. Use the washer method to set up the integral that gives the volume of the solid.
Answer: Volume = [tex]\frac{20\pi }{3}[/tex]
Step-by-step explanation: The washer method is a method to determine volume of a solid formed by revolving a region created by any 2 functions about an axis. The general formula for the method will be
V = [tex]\pi \int\limits^a_b {(R(x))^{2} - (r(x))^{2}} \, dx[/tex]
For this case, the region generated by the conditions proposed above is shown in the attachment.
Because it is revolting around the y-axis, the formula will be:
[tex]V=\pi \int\limits^a_b {(R(y))^{2} - (r(y))^{2}} \, dy[/tex]
Since it is given points, first find the function for points (3,2) and (1,0):
m = [tex]\frac{2-0}{3-1}[/tex] = 1
[tex]y-y_{0} = m(x-x_{0})[/tex]
y - 0 = 1(x-1)
y = x - 1
As it is rotating around y:
x = y + 1
This is R(y).
r(y) = 1, the lower limit of the region.
The volume will be calculated as:
[tex]V = \pi \int\limits^2_0 {[(y+1)^{2} - 1^{2}]} \, dy[/tex]
[tex]V = \pi \int\limits^2_0 {y^{2}+2y+1 - 1} \, dy[/tex]
[tex]V=\pi \int\limits^2_0 {y^{2}+2y} \, dy[/tex]
[tex]V=\pi(\frac{y^{3}}{3}+y^{2} )[/tex]
[tex]V=\pi (\frac{2^{3}}{3}+2^{2} - 0)[/tex]
[tex]V=\frac{20\pi }{3}[/tex]
The volume of the region bounded by the points is [tex]\frac{20\pi }{3}[/tex].
Ann's $6,900 savings is in two accounts. One account earns 3% annual interest and the other earns 8%. Her total interest for the year is $342. How much does she have in each account?
Answer:
x=4200, y=2700
Step-by-step explanation:
let x be first account
y the second
x+y=6900
0.03x+0.08y=342
solve by addition/elimination)
multiply first equation by 0.03
0.03x+0.03y=207 subtract from second
0.03x+0.03y-0.03x-0.08y=207-342
0.05y=135
y=2700, x=4200
g A cylindrical tank with radius 7 m is being filled with water at a rate of 6 mଷ/min. How fast is the height of the water increasing? (Recall: V = πrଶh)
Answer:
6/(49π) ≈ 0.03898 m/min
Step-by-step explanation:
V = πr²h . . . . formula for the volume of a cylinder
dV/dt = πr²·dh/dt . . . . differentiate to find rate of change
Solving for dh/dt and filling in the numbers, we have ...
dh/dt = (dV/dt)/(πr²) = (6 m³/min)/(π(7 m)²) = 6/(49π) m/min
dh/dt ≈ 0.03898 m/min
help please this is important
Answer:
D. [tex]3^3 - 4^2[/tex]
Step-by-step explanation:
Well if Alia gets 4 squared less than Kelly who get 3 cubed it’s natural the expression is 3^3 - 4 ^2