Answer:
Find the measure of what?
Step-by-step explanation:
Next time please write the entire equation. Thank you!
A concerned parent wants to determine the amount of time spent on the phone by her child's friends. Which sample is likely to bias the results of the study by reporting less than the actual time? Group of answer choices
Answer: The answers to the questions by 10 of the friends
Step-by-step explanation:
The options to the question are:
a. The answers to the questions by the parents of 10 of the friends.
b. The results of a national poll of 1800 students in the same age group as the child.
c. The answers to the questions by 10 of the friends.
d. The answers to the questions by 10 people from the parents office.
From the question, we are informed that a concerned parent wants to determine the amount of time spent on the phone by her child's friends. The sample that is likely to bias the results of the study by reporting less than the actual time is the answers to the questions by 10 of the friends.
This is because since the questions are being asked from her friends, there'll be bias as the friends won't want to give the exact time used on phone, hence, they'll hold back some information.
Find the unique solution to the following linear system X = (0 -1 2 3)X + (e' -e')
X(0)=(5 4)
It looks like the system is supposed to be
[tex]\mathbf x'=\begin{bmatrix}0&-1\\2&3\end{bmatrix}\mathbf x+\begin{bmatrix}e^t\\e^{-t}\end{bmatrix}[/tex]
with the initial condition, [tex]\mathbf x(0)=\begin{bmatrix}5&4\end{bmatrix}^\top[/tex].
Compute the eigensystem for the coefficient matrix:
[tex]\begin{vmatrix}-\lambda&-1\\2&3-\lambda\end{vmatrix}=\lambda^2-3\lambda+2=(\lambda-1)(\lambda-2)=0[/tex]
[tex]\lambda_1=1\implies\begin{bmatrix}-1&-1\\2&2\end{vmatrix}\mathbf v_1=\mathbf 0\implies\mathbf v_1=\begin{bmatrix}1\\-1\end{bmatrix}[/tex]
[tex]\lambda=2\implies\begin{bmatrix}-2&-2\\2&1\end{bmatrix}\mathbf v_2=\mathbf 0\implies\mathbf v_2=\begin{bmatrix}1\\-2\end{bmatrix}[/tex]
So we have the characteristic solution,
[tex]\mathbf x_c=C_1e^{\lambda_1t}\mathbf v_1+C_2e^{\lambda_2t}\mathbf v_2[/tex]
[tex]\mathbf x_c=C_1e^t\begin{bmatrix}1\\-1\end{bmatrix}+C_2e^{2t}\begin{bmatrix}1\\-2\end{bmatrix}[/tex]
For the non-homogeneous part, we can guess a particular solution of the form
[tex]\mathbf x_p=te^t\begin{bmatrix}a\\b\end{bmatrix}[/tex]
(We might have started with [tex]e^t[/tex] instead, but that is already accounted for in the first characteristic solution.)
Its derivative is
[tex]{\mathbf x_p}'=e^t\begin{bmatrix}a\\b\end{bmatrix}+te^t\begin{bmatrix}a\\b\end{bmatrix}=e^t\begin{bmatrix}at+a\\bt+b\end{bmatrix}[/tex]
Substitute [tex]\mathbf x_p[/tex] into the system and solve for [tex]a,b[/tex]:
[tex]e^t\begin{bmatrix}at+a\\bt+b\end{bmatrix}=te^t\begin{bmatrix}0&-1\\2&3\end{bmatrix}\begin{bmatrix}a\\b\end{bmatrix}+e^t\begin{bmatrix}1\\-1\end{bmatrix}[/tex]
[tex]\begin{bmatrix}at+a\\bt+b\end{bmatrix}=\begin{bmatrix}-bt+1\\(2a+3b)t-1\end{bmatrix}[/tex]
[tex]\implies a=1,b=-1[/tex]
and so the particular solution is
[tex]\mathbf x_p=te^t\begin{bmatrix}1\\-1\end{bmatrix}[/tex]
The general solution to the system is then
[tex]\mathbf x=\mathbf x_c+\mathbf x_p[/tex]
[tex]\mathbf x=C_1e^t\begin{bmatrix}1\\-1\end{bmatrix}+C_2e^{2t}\begin{bmatrix}1\\-2\end{bmatrix}+te^t\begin{bmatrix}1\\-1\end{bmatrix}[/tex]
Use the given initial conditions to solve for the remaining coefficients.
[tex]\mathbf x(0)=\begin{bmatrix}5\\4\end{bmatrix}[/tex]
[tex]\implies\begin{bmatrix}5\\4\end{bmatrix}=C_1\begin{bmatrix}1\\-1\end{bmatrix}+C_2\begin{bmatrix}1\\-2\end{bmatrix}[/tex]
[tex]\implies C_1=14,C_2=-9[/tex]
Then the solution to the initial value problem is
[tex]\mathbf x=14e^t\begin{bmatrix}1\\-1\end{bmatrix}-9e^{2t}\begin{bmatrix}1\\-2\end{bmatrix}+te^t\begin{bmatrix}1\\-1\end{bmatrix}[/tex]
[tex]\mathbf x=\begin{bmatrix}14e^t-9e^{2t}+te^t\\-14e^t-18e^{2t}-te^t\end{bmatrix}[/tex]
POS
In a game, two cards are drawn, and then multiplied. The winner is the person with the largest product. Explain who won the game.
-8
4
-6
-6
SOFIA
Luke
O Luke 36 < 32
O Sofia, 32 36
O Luke. -32 < 36
O Sofia, 32 - 36
Answer:
Luke, -32 < 36
Step-by-step explanation:
The two cards drawn by Sofia has values of -8 and 4 respectively. The product of her cards = -8 × 4 = -32. (Negative × positive = (negative)
The two cards drawn by Luke has values of -6 and -6 respectively. The product of his cards = -6 × -6 = 36 (negative × negative = positive).
36 greater than -32.
Luke had the largest product because -32 < 36.
In Nebraska, the mean rain-fed corn yield of harvested fields are normally
distributed, produce 147.2 bushels per acre with a standard deviation of 33 bushels per acre.
How many bushels per acre are produced if a field is in the top 25%?
O 180.2
O 125.2
O 155.45
O 169.2
Answer: 169.2 per acre are produced if a field is in the top 25%.
Step-by-step explanation:
Given: The mean rain-fed corn yield of harvested fields are normally distributed, produce 147.2 bushels per acre with a standard deviation of 33 bushels per acre.
Let X denote the mean rain-fed corn yield of harvested fields.
Let x denotes the number of bushels per acre are produced if a field is in the top 25%.
Top 25% on a density curve means , (100-25%)i.e. 75% area lies below x.
I.e.
[tex]P(X<x)=P(\dfrac{X-\mu}{\sigma}<\dfrac{x-147.2}{33})=0.75\\\\\Rightarrow\ P(Z<\dfrac{x-147.2}{33})=0.75\ \ [Z=\dfrac{X-\mu}{\sigma}][/tex].
Z-score for p-value of 0.75 (one tailed)=0.67 [By z-table]
Then, [tex]\dfrac{x-147.2}{33}=0.6744[/tex]
[tex]\Rightarrow\ {x-147.2}=33\times0.67\\\\\Rightarrow\ {x-147.2}=22.11\\\\\Rightarrow\ {x}=22.11+147.2=169.31[/tex]
Here approx value is 169.2 (from options).
So, 169.2 per acre are produced if a field is in the top 25%.
Determine if each graph represents a direct proportion or not.
Answer:
yes each paragrpah represents a direct proportion.
Step-by-step explanation:
please follow me and mark me as brainliest. please.
5√3+3√12 can anyone help me figure this out
Answer:
18.29
Step-by-step explanation:
hope this helped
Helppp please! Find the value of cos X
Answer:
3/5
Step-by-step explanation:
[tex]\cos X= \frac{XY}{ZX} = \frac{30}{50} = \frac{3}{5} \\ [/tex]
Please Explain how to do this. Will get a brainiest.
There are only a few roller coasters in the world whose path takes them underground. Suppose a portion of the roller coaster can be modeled by the function f(t) = (t2 − 13t + 40)(t2 − 2t + 3), where t represents the time elapsed in seconds since passing point A on the roller coaster and f(t) represents the height in feet above the ground. What am I supposed to write on the ticket?
Answer:
the blanks are in this order the top two are 5 and 8
then (-,+,+)
then (-,-,+)
then (+,+,+)
last (+,-,+)
Step-by-step explanation:
In the diagram below, DE is parallel to XY. What is the value of x?
ca
859
X
X
y
A. 85
o
B. 75
C. 125
D. 105
Answer:
A. 85
Step-by-step explanation:
Since DE and XY are parallel, this means that the given angle and angle x are alternate Angles. According to the law of alternate Angles, this means that they are equal. It also makes sense as the angle x is the same angle as the angle directly opposite angle 85. This is because they are on the same line across parallel lines. This also means they are equal because vertically opposite angles are always equal.
Therefore x =85
Hope this helped!
lol.Sorry I have to hurry up so my hand writing is bad i hope u can read it.
Which expression is NOT equivalent to 60+1260+12?
Answer:60+1260+13 isnt equivalent
Step-by-step explanation:
Math help! This is the only picture provided! Please find the answer!
Answer:
girl I need help with this too
Step-by-step explanation:
we both do
Please help ive been stuck on this question all weekend long !!
Answer:
The answer is 57.
Step-by-step explanation:
You have to substitute w = 2 into the expression :
[tex]8 {w}^{2} + 8w + 9[/tex]
[tex]let \: w = 2[/tex]
[tex]8 {(2)}^{2} + 8(2) + 9[/tex]
[tex] = 32 + 16 + 9[/tex]
[tex] = 57[/tex]
Answer:
57
Step-by-step explanation:
[tex]8*2^{2}+8*2+9\\8*4+16+9\\32+16+9\\48+9\\57[/tex]
Is the square root of 21 a rational number
Answer:
No
Step-by-step explanation:
But as we've stated, these prime factorizations are unique, so this can't be right. Therefore 21≠a2 , so a≠√21 , meaning that our earlier assumption of √21 being rational turns out to be wrong, therefore √21 is irrational.
Find an equation of the line through (3,8) and parallel to y = 4x - 3.
Answer: y=4x-4
Step-by-step explanation:
To find the equation fo the line parallel to the given line, we can use the given point to find the y-intercept. We know that the slope must stay the same because parallel lines NEVER touch or cross. This means that the slope MUST be the same.
y=4x+b
We can use the given point to find the y-intercept.
8=4(3)+b [multiply]
8=12+b [subtract both sides by 12]
b=-4
Now that we have found the y-intercept, we can complete the equation.
y=4x-4
The scale from an actual triangle to the drawing at the right is 30:1. The scale from the same triangle to Jorge's drawing of the triangle is 101. Is this drawing or Jorge's drawing larger? Explain your answers.
Answer:
The actual triangle is larger
Step-by-step explanation:
Given
[tex]Scale = Actual Triangle : Drawing[/tex]
[tex]Scale = 30 : 1[/tex]
[tex]Jorge = 101[/tex]
Required
Determine which is bigger
The answer to this question can be extracted from the given scale.
The question says: the scale from the actual triangle to the drawing is 30 : 1.
This implies that;
If Jorge's drawing is 101, then the actual length is 30 * 101 =3030
Since, 3030 > 30, then
We cam conclude that the actual triangle is bigger
3 – (–3) + 7 – 4 =
A)
14
B)
12
C)
2
D)
9
Answer:
D) 9Step-by-step explanation:
[tex]3 - (-3) + 7 - 4 =\\\mathrm{Follow\:the\:PEMDAS\:order\:of\:operations}\\\\\mathrm{Add\:and\:subtract\:\left(left\:to\:right\right)}\:\:\\\\\mathrm{Apply\:rule\:}-\left(-a\right)\:=\:+a\\\\-\left(-3\right)=+3\\\\=3+3+7-4\\\\3+3=6\\\\=6+7-4\\\\6+7=13\\\\=13-4\\\\13-4\\=9[/tex]
Raise the fraction to higher terms indicated 9/20 to fortieths
Answer:
18/40
Step-by-step explanation:
You multiply the denominator by 2 and the numerator by 2 to get 18/40
The graph shows the distribution of weights (in pounds) of male duck-billed platypuses. The distribution is approximately Normal, with a mean of 3.75 pounds and a standard deviation of 0.52 pounds. What percent of male duck-billed platypuses have a weight of between 2.71 and 4.79 pounds?
Answer:
Choice B) The distribution is approximately Normal, with a mean of 3.75 pounds and a standard deviation of 0.52 pounds.
Step-by-step explanation:
Using the normal distribution principle, the percentage with weight between 2.71 and 4.79 is 95.45%
Using the Zscore relation :
Zscore = (X - μ) ÷ σFor X = 2.71 :
Zscore = (2.71 - 3.75) ÷ 0.52 = - 2
Using a normal distribution table :
P(Z < - 2) = 0.02275
For X = 4.79 :
Zscore = (4.79 - 3.75) ÷ 0.52 = 2
Using a normal distribution table :
P(Z < 2) = 0.97725
P(Z < 2) - P(Z < - 2) = 0.97725 - 0.02275 = 0.9545
Therefore, the required percentage is 95.45%
Learn more : https://brainly.com/question/15139545
Select the best answer for the question.
11. Which of the following human relations skills is most clearly related to communication?
O A. Responsibility
O B. Listening
O C. Drive
O D. Self-confidence
Mark for review (Will be highlighted on the review page)
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Answer:
Listening
Step-by-step explanation:
The others are good qualities too, but first you need to listen to other people and have them listen to you. It's one of the first steps of communicating well with other people.
Answer this for me ........
Is f(x) = 3x2 - 6x + 2 an example of a quadratic?
Yes
No
The length of a rectangle is 6 more than its width. The perimeter is 48 inches. What is the length?
Answer:
[tex]15[/tex] inches
Step-by-step explanation:
Let the width be x.
Length = [tex]6+x[/tex]
Perimeter = Length + Length + Breadth + Breadth
Perimeter = [tex](6+x)+(6+x)+x+x=48[/tex]
[tex]6+x+6+x+x+x=48[/tex]
[tex]4x+12=48[/tex]
Subtract 12 from both sides:
[tex]4x+12-12=48-12[/tex]
[tex]4x=36[/tex]
Divide both sides by 4:
[tex]\frac{4x}{4}=\frac{36}{4}[/tex]
[tex]x=9[/tex] (Width)
Length = [tex]9+6=15[/tex] inches.
Answer:
l = 15 inches
Step-by-step explanation:
l = w + 6
p = 2l + 2w
substitute l into equation p
48 = 2(w + 6) + 2w
distribute the 2 into the parentheses
48 = 2w + 12 + 2w
combine like terms
48 = 4w + 12
subtract 12 from both sides
36 = 4w
divide by 4
9 = w
plug w into equation l
(9) + 6 = 15
l = 15 inches
solve screen shot attachment EASY
Answer:
x=w/(56+r)
Step-by-step explanation:
19x+rx=-37x+w
19x+rx+37x=w
x(19+37+r)=w
x(56+r)=w
x=w/(56+r)
if anything is unclear, ask freely.
Two groups collect litter along the side of a road. It takes each group 5 minutes to clean up a 200-yard section. How long does it take to clean up 2 miles?
It takes__minutes to clean up 2 miles.
HELPPPP!!!!!!!!!!!!!
Each group can clean 200 ÷ 5 = 40 yards each minute, so together the two groups can clean 80 yards each minute. So, it takes 3520 ÷ 80 = 44 minutes to clean 2 miles.
A right rectangular prism has a base area of 2 1/2 square inches and a height of 11 1/2 inches.
What is the volume of the prism?
Answer:14in 3
Step-by-step explanation:
Paul won 128 super bouncy balls playing
horseshoes at the county fair. At school he
gave four to every student in his math class.
He only has 4 remaining. How many
students are in his class?
solve 6x^3-7x^2-5x=0
Factor the x out first:
x(6x^2 - 7x - 5) = 0
Then factor the quadratic expression in the parenthesis:
x(2x + 1)(3x - 5) = 0
x = -1/2, 0, 5/3
4/5 × 2 3/8 - 2 × 3/5
A poultry farmer wishes to estimate the average incubation period (the number of days between a hen laying her egg and the time the egg hatches) for eggs on his farm. He plans to take a sample and make a 98% confidence interval, and would like a margin of error of half a day. It is known that the distribution of incubation lengths has a standard deviation of 1.5 days. How many eggs does he need to sample to create the desired interval
Answer:
49 eggs.
Step-by-step explanation:
The formula for Margin of Error =
z × standard deviation/√number of samples
z = z score of 98% confidence interval = 2.326
Margin of Error = Half a day = 1/2day = 0.5 day
Standard deviation = 1.5 days
Number of samples = number of eggs he needs to sample = unknown.
Imputing these above values into the formula
Margin of Error = z × standard deviation/√number of samples
0.5 = 2.326 × 1.5/√n
Cross Multiply
0.5 × √n = 2.326 × 1.5
√n = 2.326 × 1.5/0.5
√n = 3.489/0.5
√n = 6.978
Square both sides
(√n)² = 6.978²
n = 48.692484
n ≈ Approximately to the nearest whole number = 49
Therefore, the number of eggs he needs to sample to create the desired interval is approximately to the nearest whole number 49 eggs
