Answer:
b
Step-by-step explanation:
Because only the customers who spend more than $100 get to complete the form. The other customers wont be able to complete it(people who spent less than $100). thats why the answer would be sampling bias.
The Richter scale measures the magnitude, M, of an earthquake as a function of its intensity, I, and the intensity of a reference earthquake, .
Which equation calculates the magnitude of an earthquake with an intensity 10,000 times that of the reference earthquake?
Answer:
Option B. M = Log 10000
Step-by-step explanation:
From the question given above, we were told that the intensity (I) is 10000 times that of the reference earthquake (I₀).
Thus, we can obtain the magnitude (M) of the earthquake as follow:
Let the reference earthquake (I₀) = A
Then, the intensity (I) = 10000 × A
M = Log(I/I₀)
M = Log(10000A / A)
M = Log 10000
Thus, option B gives the right answer to the question.
n eight-sided die, which may or may not be a fair die, has four colors on it; you have been tossing the die for an hour and have recorded the color rolled for each toss. What is the probability you will roll a blue on your next toss of the die
Answer:
The answer is "21%".
Step-by-step explanation:
[tex]\to 26 + 20 + 29 + 49 = 124\\\\=\frac{26\ \text{brown times}}{124 \ \text{total times}} \\\\= \frac{26}{ 124} \\\\ = 0.209677 \\\\[/tex]
Calculating the percentage:
[tex]= 20.9677 \times 100\\\\=20.9677\% \approx 21\%[/tex]
What is the image of (-4, -12) after a dilation by a scale factor of centered at the 1/4 origin?
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Answer:
(-1, -3)
Step-by-step explanation:
Each coordinate is multiplied by the dilation factor when dilation is centered at the origin.
(1/4)(-4, -12) = (-1, -3) . . . . the image of the given point
Hey good morning I need help ASAP thank you guys
Answer:
B. x = 2.77
Step-by-step explanation:
3^x = 21
You first look for a base for 21 that is 3 to the power of something.
21 = 3^2.77
So 3^x = 2^2.77
They have the same base so
x= 2.77
Find the values for x and y using the diagram below. Explain what geometric relationships you used to solve the problem.
You DO NOT have to write a proof. An example would be "linear pair" or "right angles= 90◦
".
Answer:
2x, a linear pair
Step-by-step explanation:
2/5x/3/4 = 7/4 = 1 3/4
FX) is defined by the equation f(x) = 4x2 - 2x +17. What effect will multiplying
f(x) by 0.5 have on the graph?
A. The graph will be stretched horizontally.
B. The graph will be compressed horizontally.
C. The graph will be stretched vertically.
D. The graph will be compressed vertically.
Step-by-step explanation:
the graph will be compressed vertically
Roger can shovel his family's driveway in 1 hour. His older sister, Alexis, can shovel the driveway in 1/2 hour. If they work together, then how many minutes will it take them to shovel the driveway?
Answer:
40 min
Step-by-step explanation:
his sister can do it twice as fast so the boy does 1 and the sister does 2. he will do 1/3 of the work and it will take 1/3 of the time
Answer:
90 mins
Step-by-step explanation:
1 hour =60 mins
1/2 hour = 60/2=30
so, 60 +30=90
Write an equation for the graph below in terms of x
Answer:
x = -2
Step-by-step explanation:
the line goes through -2 on the x-axis
the line also goes through -3 on the y-axis
solve 3x-4=√(2x^2-2x+2)
Answer:
Step-by-step explanation:
Begin the solution by squaring both sides of the given equation. We get:
(3x - 4)^2 = 2x^2 - 2x + 2, or:
9x^2 - 24x + 16 = 2x ^2 - 2x + 2
Combining like terms results in:
7x^2 - 22x + 14 = 0
and the coefficients are a = 7, b = -22, c = 14, so that the discriminant of the quadratic formula, b^2 - 4ac becomes (-22)^2 - 4(7)(14) = 92
According to the quadratic formula, the solutions are
-b ± √discriminant -(-22) ± √92 22 ± √92
x = ------------------------------- = ----------------------- = ------------------------
2a 14 14
solve the following equations
Answer:
x=0,5/2
Step-by-step explanation:
Is the following equation graph a linear function a non linear function and or a relation
Answer:
Step-by-step explanation:
Functions are always relations, but not every relation is a function. This passes the vertical line test so it is a function. Since it's not a line, it's not linear. B is your choice.
Jordan buys sandals and sunglasses for a trip to the beach. The sunglasses cost $6. The sandals cost 3 times as much as the sunglasses. How much do the sandals cost?
Answer:
18 dollars
Step-by-step explanation:
sunglasses = 6 dollars
sandals = 3 * sunglasses
= 3 * 6 dollars
= 18 dollars
Consider the distribution Ber(0.25). Consider the categorical statistical model({a1,..., ax},{Pp}) for this Bernoulli distribution. If we let Q1 = 1 and a2 =0, then this corresponds to a categorical distribution P, with parameter vector p given by:______.
a. 0.25
b. 0.75
c. (0.25 0.75]^T
d. [0.75 0.25)^T
Answer:
c. [0.25 0.75] ^T
Step-by-step explanation:
Bernoulli distribution is used to identify number of successes and failures in the selected sample. In the given problem Ber distribution trial is 0.25. There will be categorical distribution of 0.75 and the trial will be done on parameter vector.
A television camera is positioned 4000 ft from the base of a rocket launching pad. The angle of elevation of the camera has to change at the correct rate in order to keep the rocket in sight. Also, the mechanism for focusing the camera has to take into account the increasing distance from the camera to the rising rocket. Let's assume the rocket rises vertically and its speed is 800 ft/s when it has risen 3000 ft. (Round your answers to three decimal places.)
(a) How fast is the distance from the television camera to the rocket changing at that moment?
ft/s
(b) If the television camera is always kept aimed at the rocket, how fast is the camera's angle of elevation changing at that same moment?
rad/s
============================================
Explanation for part (a)
t = time in secondsx = horizontal distance from the camera to the launch pady = vertical distance from the launch pad to the rocket's locationz = distance from camera to the rocket at time tAll distances mentioned are in feet.
We'll have a right triangle which allows us to apply the pythagorean theorem. Refer to the diagram below.
a^2+b^2 = c^2
x^2+y^2 = z^2
Apply the derivative to both sides with respect to t. We'll use implicit differentiation and the chain rule.
[tex]x^2+y^2 = z^2\\\\\frac{d}{dt}[x^2+y^2] = \frac{d}{dt}[z^2]\\\\\frac{d}{dt}[x^2]+\frac{d}{dt}[y^2] = \frac{d}{dt}[z^2]\\\\2x*\frac{dx}{dt}+2y*\frac{dy}{dt}=2z*\frac{dz}{dt}\\\\x*\frac{dx}{dt}+y*\frac{dy}{dt}=z*\frac{dz}{dt}\\\\[/tex]
Now we'll plug in (x,y,z) = (4000,3000,5000). The x and y values are given. The z value is found by use of the pythagorean theorem. Ie, you solve 4000^2+3000^2 = z^2 to get z = 5000. Or you could note that this is a scaled copy of the 3-4-5 right triangle.
We know that dx/dt = 0 because the horizontal distance, the x distance, is not changing. The rocket is only changing in the y direction. Or you could say that the horizontal speed is zero.
The vertical speed is dy/dt = 800 ft/s and it's when y = 3000. It's likely that dy/dt isn't the same value through the rocket's journey; however, all we care about is the instant when y = 3000.
Let's plug all that in and isolate dz/dt
[tex]4000*0+3000*800=5000*\frac{dz}{dt}\\\\2,400,000=5000*\frac{dz}{dt}\\\\\frac{dz}{dt} = \frac{2,400,000}{5000}\\\\\frac{dz}{dt} = 480\\\\[/tex]
At the exact instant that the rocket is 3000 ft in the air, the distance between the camera and the rocket is changing by an instantaneous speed of 480 ft/s.
-----------------------------------------------------------------------
Explanation for part (b)
Again, refer to the diagram below.
We have theta (symbol [tex]\theta[/tex]) as the angle of elevation. As the rocket's height increases, so does the angle theta.
We can tie together the opposite side y with the adjacent side x with the tangent function of this angle.
[tex]\tan(\text{angle}) = \frac{\text{opposite}}{\text{adjacent}}\\\\\tan(\theta) = \frac{y}{x}[/tex]
Like before, we'll apply implicit differentiation. This time we'll use the quotient rule as well.
[tex]\tan(\theta) = \frac{y}{x}\\\\\frac{d}{dt}[\tan(\theta)] = \frac{d}{dt}\left[\frac{y}{x}\right]\\\\\sec^2(\theta)*\frac{d\theta}{dt} = \frac{\frac{dy}{dt}*x - y*\frac{dx}{dt}}{x^2}\\\\\sec^2(\theta)*\frac{d\theta}{dt} = \frac{800*4000 - 3000*0}{4000^2}\\\\\sec^2(\theta)*\frac{d\theta}{dt} = \frac{3,200,000}{16,000,000}\\\\\sec^2(\theta)*\frac{d\theta}{dt} = \frac{32}{160}\\\\\sec^2(\theta)*\frac{d\theta}{dt} = \frac{1}{5}\\\\[/tex]
Let's take a brief detour. We'll return to this later. Recall earlier that [tex]\tan(\theta) = \frac{y}{x}\\\\[/tex]
If we plug in y = 3000 and x = 4000, then we end up with [tex]\tan(\theta) = \frac{3}{4}\\\\[/tex] which becomes [tex]\tan^2(\theta) = \frac{9}{16}[/tex]
Apply this trig identity
[tex]\sec^2(\theta) = 1 + \tan^2(\theta)[/tex]
and you should end up with [tex]\sec^2(\theta) = 1+\frac{9}{16} = \frac{25}{16}[/tex]
So we can now return to the equation we want to solve
[tex]\sec^2(\theta)*\frac{d\theta}{dt} = \frac{1}{5}\\\\\frac{25}{16}*\frac{d\theta}{dt} = \frac{1}{5}\\\\\frac{d\theta}{dt} = \frac{1}{5}*\frac{16}{25}\\\\\frac{d\theta}{dt} = \frac{16}{125}\\\\\frac{d\theta}{dt} = 0.128\\\\[/tex]
This means that at the instant the rocket is 3000 ft in the air, the angle of elevation theta is increasing by 0.128 radians per second.
This is approximately 7.334 degrees per second.
The distance from the television camera to the rocket is changing at 480 ft/s while the camera's angle of elevation is changing at 0.128 rad/s
Let x represent the distance from the camera to the rocket and let h represent the height of the rocket.
a)
[tex]x^2=h^2+4000^2\\\\2x\frac{dx}{dt}=2h\frac{dh}{dt} \\\\x\frac{dx}{dt}=h\frac{dh}{dt} \\\\At \ h=3000\ ft, \frac{dh}{dt}=800\ ft/s;\\x^2=3000^{2} +4000^2\\x=5000\\\\\\x\frac{dx}{dt}=h\frac{dh}{dt} \\\\5000\frac{dx}{dt}=3000*800\\\\\frac{dx}{dt}=480\ ft/s[/tex]
b)
[tex]tan(\theta)=\frac{h}{4000} \\\\h=4000tan(\theta)\\\\\frac{dh}{dt}=4000sec^2(\theta)\frac{d\theta}{dt} \\\\\\At\ h=3000\ ft;\\\\tan\theta = \frac{3000}{4000}=\frac{3}{4} \\\\sec^2(\theta)=1+tan^2(\theta)=1+(\frac{3}{4})^2=\frac{25}{16} \\\\\\\frac{dh}{dt}=4000sec^2(\theta)\frac{d\theta}{dt}\\\\800=4000*\frac{25}{16}* \frac{d\theta}{dt}\\\\\frac{d\theta}{dt}=0.128\ rad/s[/tex]
Hence, The distance from the television camera to the rocket is changing at 480 ft/s while the camera's angle of elevation is changing at 0.128 rad/s
Find out more at: https://brainly.com/question/1306506
If the slope of a wheelchair ramp is 1/11 then what is the angle of inclination to the nearest tenth of a degree?
Answer
4.8 degrees to the nearest tenth.
Step-by-step explanation:
The slope = rise / run = opposite side / adjacent side.
So the angle of inclination is the angle whose tangent is 1/12.
To the nearest tenth of a degree it is 4.8 degrees.
Illustrate the 7th pattern of the sequence of square numbers.
1,4,9,16,25,36,49,........
7th pattern =49.....
Answer:
1, 4, 9, 16, 25, 36, 49…................the 7 the pattern is 49
Determine the remaining sides and angles of the triangle ABC.
c=6 mi, B = 38.71°, C = 32.51°
Find the measure of angle A.
A=°
(Type an integer or a decimal.)
Find the length of side a.
а:
mi
(Round to the nearest mile as needed.)
Find the length of side b.
b=mi
(Round to the nearest mile as needed.)
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Answer:
A = 108.78°
a = 11 mi
b = 7 mi
Step-by-step explanation:
The sum of angles in a triangle is 180°, so the third angle is ...
A = 180° -38.71° -32.51°
A = 108.78°
__
The remaining sides can be found from the law of sines.
a/sin(A) = c/sin(C)
a = sin(A)·c/sin(C) ≈ 0.946762 × 11.163896
a ≈ 11 mi
b = sin(B)·11.163896 ≈ 0.625379 × 11.163896
b ≈ 7 mi
Jeanne has a coupon for 1.95 off a jug of name brand laundry detergent that normally costs 14.99 . The store brand laundry detergent costs 11.53 How much will Jeanne save if she buys the store brand detergent instead of using her coupon and buying the name brand
Step-by-step explanation:
14.99 - 11.53= 3.46+1.95 =4.41
Find the missing side. Round your answer to the nearest tenth.
Answer:
[tex]sin\left(90\right)/x=sin\left(25\right)/16[/tex]
x = 37.85
Step-by-step explanation:
Find the fraction equivalent to 5/7 with: a) numerator 25 b) denominator 42
Answer:
a) 25/35
b) 30/42
Step-by-step explanation:
a)
Variable x = denominator if numerator is 25
5/7 = 25/x
5 × x = 7 × 25
5x = 175
x = 35
b)
Variable y = numerator if denominator is 42
5/7 = y/42
5 × 42 = 7 × y
210 = 7y
30 = y
25/35
30/42
To get 25/35 multiply by 5
To get 30/42 multiply by 6
The data show the traveler spend- ing in billions of dollars for a recent year for a sample of the states. Find the range, variance, and standard deviation for the data.
20.1 33.5 21.7 58.4 23.2 110.8 30.9
24.0 74.8 60.0
Solution :
Given data :
20.1 33.5 21.7 58.4 23.2 110.8 30.9
24.0 74.8 60.0
n = 10
Range : Arranging from lowest to highest.
20.1, 21.7, 23.2, 24.0, 30.9, 33.5, 58.4, 60.0, 74.8, 110.8
Range = low highest value - lowest value
= 110.8 - 20.1
= 90.7
Mean = [tex]$\frac{\sum x}{n}$[/tex]
[tex]$=\frac{20.1+21.7+23.2+24.0+30.9+33.5+58.4+60.0+74.8+110.8}{10}$[/tex]
[tex]$=\frac{457.4}{10}$[/tex]
[tex]$=45.74$[/tex]
Sample standard deviation :
[tex]$S=\sqrt{\frac{1}{n-1}\sum(x-\mu)^2}$[/tex]
[tex]$S=\sqrt{\frac{1}{10-1}(20.1-45.74)^2+(21.7-45.74)^2+(23.2-45.74)^2+(24.0-45.74)^2+(30.9-45)^2}$[/tex]
[tex]\sqrt{(33.5-45.74)^2+(58.4-45.74)^2+(60.0-45.74)^2+(74.8-45.74)^2+(110.8-45.74)^2}[/tex]
[tex]$S=\sqrt{\frac{1}{9}(657.4+577.9+508.0+472.6+220.2+149.8+160.2+203.3+844.4+4232.8)}$[/tex][tex]$S=\sqrt{\frac{1}{9}(8026.96)}$[/tex]
[tex]$S=\sqrt{891.88}$[/tex]
S = 29.8644
Variance = [tex]S^2[/tex]
[tex]=(29.8644)^2[/tex]
= 891.8823
factorise m^2 - 12 m + 24
Answer:
(m-6+2root3)(m-6-2root3)
Step-by-step explanation:
m^2 - 12m +36 -12
= (m-6)^2 - 12
= (m-6+2root3)(m-6-2root3)[root 12 = 2root3]
What are the zeros of this function?
Answer:
The zeros of this function would be: x = 4 and x = 6, assuming that option got caught off while you were taking a picture.
Step-by-step explanation:
When they're asking for the zeros of this type of function, where is forms this kind of U-shape or also known as a quadratic equation, they're asking what the x-value is when y = 0, or when the line of the function touches the x-axis. Notice that it happens when x = 4 and when x = 6.
In short, it's asking what the x-value is of the points of the function when it intersects the x-axis. Hopefully my explanation wasn't too confusing. Good luck on the rest of the quiz!
The increase in length of an aluminum rod is twice the increase in length of an Invar rod with only a third of the temperature increase. Find the ratio of the lengths of the two rods.
Answer:
the ratio of lengths of the two rods, Aluminum to Invar is 11.27
Step-by-step explanation:
coefficient of linear expansion of aluminum, [tex]\alpha _{Al} = 23 \times 10^{-6} /K[/tex]
Coefficient of linear expansion of Invar, [tex]\alpha _{Iv} = 1.2 \times 10^{-6}/K[/tex]
Linear thermal expansion is given as;
[tex]\Delta L = L_0 \times \alpha\times \Delta T\\\\where;\\\\L_0 \ is \ the \ original \ length \ of \ the \ metal\\\\\Delta L \ is \ the \ increase \ in \ length[/tex]
The increase in length of Invar is given as;
[tex]\Delta L_{Iv} = L_0_{Iv} \times \alpha _{Iv}\times \Delta T_{Iv}[/tex]
The increase in length of the Aluminum;
[tex]\Delta L_{ Al} = L_0_{Al} \times \alpha _{Al} \times \Delta T_{Al}\\\\from \ the\ given \ question, \ the \ relationship \ between \ the \ rods \ is \ given \ as\\\\ L_0_{Al} \times \alpha _{Al} \times \frac{1}{3} \Delta T_{Iv}= 2( L_0_{Iv} \times \alpha _{Iv} \times \Delta T_{Iv})\\\\ L_0_{Al} \times \alpha _{Al} \times \Delta T_{Iv}= 6( L_0_{Iv} \times \alpha _{Iv} \times \Delta T_{Iv})\\\\ L_0_{Al} \times \alpha _{Al} \times \Delta T_{Iv} = 6L_0_{Iv} \times 6\alpha _{Iv} \times 6 \Delta T_{Iv}\\\\[/tex]
[tex]\frac{L_0_{Al}}{6L_0_{Iv} } = \frac{6\alpha _{Iv} \ \times \ 6 \Delta T_{Iv}}{\alpha _{Al} \ \times \ \Delta T_{Iv}} \\\\\frac{L_0_{Al}}{6L_0_{Iv} } = \frac{6\alpha _{Iv} \ \times \ 6}{\alpha _{Al} \ } \\\\\frac{L_0_{Al}}{L_0_{Iv} } = 6^3(\frac{\alpha _{Iv} }{\alpha _{Al} } )\\\\\frac{L_0_{Al}}{L_0_{Iv} } = 6^3(\frac{1.2 \times 10^{-6} }{23\times 10^{-6} } )\\\\\frac{L_0_{Al}}{L_0_{Iv} } = 6^3(\frac{1.2}{23} )\\\\\frac{L_0_{Al}}{L_0_{Iv} } = \frac{259.2}{23} \\\\\frac{L_0_{Al}}{L_0_{Iv} } = 11.27[/tex]
Therefore, the ratio of lengths of the two rods, Aluminum to Invar is 11.27
The ratio of the lengths of the two rods which is length of aluminum to length of Invar rod is; 11.27
Formula for linear thermal expansion is;
ΔL = L × α × ΔT
Where;
ΔL is change in original length
L is original length
α is coefficient of linear expansion
ΔT is change in temperature
We are told that increase in length of aluminum rod is twice the increase in length of an Invar rod with only a third of the temperature increase.
Thus;
ΔL = 2ΔL
ΔT for the aluminum rod = ⅓ΔT for the Invar rod.
Thus, we have;
L_al × α_al × ⅓ΔT = 2L_in × 2α_in × 2ΔT
ΔT will cancel out to give;
⅓(L_al × α_al) = 2L_in × 2α_in × 2
Multiply both sides by 3 to get;
(L_al × α_al) = 6L_in × 6α_in × 6
From online tables, the linear coefficient of expansion of aluminum is 23 × 10^(-6) C¯¹
While the coefficient of thermal expansion for Invar rod is 1.2 × 10^(-6) K¯¹
Thus;
L_al × 23 × 10^(-6) = 6L_in × (6 × 1.2 × 10^(-6)) × 6
L_al/L_in = (6 × 6 × 1.2 × 10^(-6) × 6)/(23 × 10^(-6))
L_al/L_in = 11.27
Read more on coefficient of linear expansion at; https://brainly.com/question/6985348
I have a final for summer schoollll due midnight and it’s 10:23!!!!!!!!!!!!
Solve 9(7x-2) = 5 (10x - 1)
Answer:
[tex]9(7x - 2) = 5(10x - 1) \\ \\ 63x - 18 = 50x - 5 \\ \\ 63x - 50x = - 5 + 18 \\ \\ 13x = - 5 + 18 \\ \\ 13x = 13 \\ \\ x = \frac{13}{13} \\ \\ x = 1[/tex]
Answer:
[tex]9(7x - 2) = 5(10x - 1) \\ 9 \times 7x - 9 \times 2 = 5 \times 10x - 5 \\ 63x - 18 = 50x - 5 \\ 63x - 50x = - 5 + 18 \\ 13x = 13 \\ x = 1 \\ thank \: you[/tex]
20 POINTS! The answer is x=4 and x= -5, how should I word it, saying how he is wrong?
Answer:
The student took the numbers for the factors 5, -4 for the zeros instead of solving the equation
The zeros are -5, 4
Step-by-step explanation:
x^2 +x - 20=0
What 2 number multiply to -20 and add to 1
5*-4 = -20
5+-4 = 1
(x+5)(x-4) =0
Using the zero product property
x+5 = 0 x-4 =0
x=-5 x=4
Answer:
Solution given:
equation is:
x²+x-20=0
doing middle term factorisation
note:we need to get 1 while subtracting factor of the product of constant and coefficient of x².
20*1=20=2*5*2*1
we get 1 while subtracting 5-2*2=5-4
now substitute value 5-4 at coefficient of x
we get
x²+(5-4)x-20=0
now
distribute
x²+5x-4x-20=0
taking common from each two term
x(x+5)-4(x+5)=0
again taking common (x+5) and keeping remaining at another bracket
(x+5)(x-4)=0
either
x+5=0
x=-5
or
x-4=0
x=4
Error is:
x= 4 not -4
x=-5 not 5.
I need you guy’s help answer thanks so much
Answer:
Yes 7i is the answer
Step-by-step explanation:
they are equivalent.
Let U be a matrix where u_ij = 0 if i > j, and L be a matrix where l_ij = 0 if i < j.
(a) U is called an upper triangular matrix and L is a lower tri-angular matrix. Explain why.
(b) Prove or disprove: The sum of two upper triangular matrices is an upper triangular matrix.
(c) Prove or disprove: The product of two upper triangular matrices is an upper triangular matrix.
Answer:
A) U is called an upper triangular matrix because all entries below the principal diagonal element are zeros ( 0 ) since Uij = 0 if i >j also
L is a lower triangular matrix because all entries above the principal diagonal element are zero ( 0 )
B) sum of two upper triangular matrices = upper triangular matrix.
C) product of two upper triangular matrices = upper triangular matrix
Step-by-step explanation:
A) U is called an upper triangular matrix because all entries below the principal diagonal element are zeros ( 0 ) since Uij = 0 if i >j also
L is a lower triangular matrix because all entries above the principal diagonal element are zero ( 0 ) since Lij = 0 if i < j
B) To prove that sum of two upper triangular matrices
attached below
C) Prove or disprove that product of two upper triangular matrices is an upper triangular matrix
attached below
Work out m and c for the line: y = 6 x
Answer:
m = 6
c = 0
General Formulas and Concepts:
Algebra I
Slope-Intercept Form: y = mx + c
m - slope c - y-interceptStep-by-step explanation:
Step 1: Define
y = 6x
↓ Compare to Slope-Intercept Form
Slope m = 6
y-intercept c = 0
