Answer:
The correct option is (A).
Step-by-step explanation:
If the reduced row echelon form of the coefficient matrix of a linear system of equations in four different variables has a pivot, i.e. 1, in each column, then the reduced row echelon form of the coefficient matrix is say A is an identity matrix, here I₄, since there are 4 variables.
[tex]\left[\begin{array}{cccc}1&0&0&0\\0&1&0&0\\0&0&1&0\\0&0&0&1\end{array}\right][/tex]
Then the corresponding augmented matrix [ A|B] , where the matrix is the representation of the linear system is AX = B, must be:
[tex]\left[\begin{array}{ccccc}1&0&0&0&a\\0&1&0&0&b\\0&0&1&0&c\\0&0&0&1&d\end{array}\right][/tex]
Now the given linear system is consistent as the right most column of the augmented matrix is a linear combination of the columns of A as the reduced row echelon form of A has a pivot in each column.
Thus, the correct option is (A).
The population of Boomtown is currently 3000 and expected to grow by 2.3% over the
next year. What will its population be by then?
The population of Dullsville, on the other hand, is currently 13000 and expected to
decrease by 4.1% over the next year. What will its population be by then?
Answer:
a) The Expectation of the Population to grow in the next year
= 3069
b) The Expectation of the Population decrease in the next year
= 12,467
Step-by-step explanation:
Explanation:-
a)
The population of Boom town is currently 3000
Given expected to grow by 2.3 % over the next year
= [tex]3000 X \frac{2.3}{100} = 69[/tex]
= 69
The Expectation of the Population growth in the next year
= 3000 +69 = 3069
b)
The population of town is currently 13000
Given expected to grow by 4.1 % over the next year
= [tex]13000 X \frac{4.1}{100} = 533[/tex]
The Expectation of the Population decrease in the next year
= 13000 - 533 = 12,467
Wisconsin Public Radio wants to duplicate a survey conducted in 2011 that found that 68% of adults living in Wisconsin felt that the country was going in the wrong direction. How many people would need to be surveyed for a 90% confidence interval to ensure the margin of error would be less than 3%? Be sure to show all your work and round appropriately
Answer:
655 people would need to be surveyed.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
In this question, we have that:
[tex]\pi = 0.68[/tex]
The margin of error is:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
90% confidence level
So [tex]\alpha = 0.1[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.1}{2} = 0.95[/tex], so [tex]Z = 1.645[/tex].
How many people would need to be surveyed for a 90% confidence interval to ensure the margin of error would be less than 3%?
We need to survey n adults.
n is found when M = 0.03. So
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.03 = 1.645\sqrt{\frac{0.68*0.32}{n}}[/tex]
[tex]0.03\sqrt{n} = 1.645\sqrt{0.68*0.32}[/tex]
[tex]\sqrt{n} = \frac{1.645\sqrt{0.68*0.32}}{0.03}[/tex]
[tex](\sqrt{n})^{2} = (\frac{1.645\sqrt{0.68*0.32}}{0.03})^{2}[/tex]
[tex]n = 654.3[/tex]
Rounding up
655 people would need to be surveyed.
Which of the options is the response variable?
A. The number of adults.
B. The type of training exercises performed by each participant.
C. The size of the physiological blind spot.
D. The number of times an adult performed training exercises.
Question:
The physiological blind spot refers to a very small zone of functional blindness in the eye where the optic nerve passes through the retina. We do not notice it because our nervous system compensates for it. Can eye training reduce the size of a person's physiological blind spot? Researchers recruited a representative sample of 10 adults with normal vision. Each participant performed training exereises with one eye for three weeks. The size of the physiological blind spot was measured (in degrees of visual angle squared) with a motion detection task both prior to training and again after the training was completed. Which of the options is the response variable?
A) The size of the physiological blind spot
B) The number of adults.
C) The type of training exercises performed by each participant.
D) The size of the physiological blind spot.
E) The number of times an adult performed training exercises.
Answer:
The correct answer is A)
Explanation:
The response variable (when experimenting) is the variable or factor about which the researcher is concerned. It can also be (as the name entails) the variable which respond to changes in the experiment.
The changes in the experiment is the training. The variable which the researcher is concerned about and which may or may not change with the introduction of training is the size of the physiological blind spot.
Cheers!
If an icecream cone starts at $2 and an additional $0.50 for each scoop, what is
the cost of a 3-scoop cone?
Answer:
$3.50
Step-by-step explanation:
$2 + (3 x $0.50) = x
$2 + $1.50 = x
x = $3.50
Answer:$3:50
Step-by-step explanation: 2+0.50+0.50=3+0.50=$3.50
How many days are there in 12 weeks? Use the following information to convert this time to days. 1 week = 7 days
Answer:
84days
Step-by-step explanation:
1 week = 7days =>12 weeks = 12×7 = 84days
Answer:
84 days are in 12 weeks
Step-by-step explanation:
1 week = 7 days
4 weeks = 28 days
So 28 + 28 + 28 = 84 days
What is the MEDIAN of this data?
Answer:
I think the median is 7
if it is not im so sorry
The median of the data is 7.
please see the attached picture for full solution
Hope it helps
Good luck on your assignment
What is the general form of this equation:
The line passes through the point (-2,4) with a slope -2/3
Answer: y= -2/3 + 8/3
Step-by-step explanation:
-2/3 is the slope so you just need the y-intercept to write the equation in general form or slope intercept form
4= -2/3(-2) +b
4 = 4/3 + b
-4/3 -4/3
b= 8/3
general form is y= -2/3 + 8/3
is 7.68 bigger than 7.680
Answer:
literally 7.68=7.680
someone pls help me ! i rlly need help
Answer:
Option D is the correct answer.
Step-by-step explanation:
Coefficients od dividend = (4, - 17, - 15)
Dividend [tex]=4x^2 - 17x - 15[/tex]
Divisor x = 5 =>x-5= 0
Coefficients of Quotient = (4, 3)
Quotient [tex]=4x + 3[/tex]
Remainder = 0
Since,
[tex] Dividend = Divisor \times quotient + Remainder\\
\therefore 4x^2 - 17x - 15 = (x - 5)\times (4x + 3) +0 \\
\therefore 4x^2 - 17x - 15 = (x - 5)\times (4x + 3) \\
\therefore( 4x^2 - 17x - 15) \div (x - 5) = (4x + 3)
[/tex]
HI!!! CAN SOMEONE HELP ME ON GRAPHING THIS? THANKS, i WILL GIVE YOU 5 STARS AND OTHERS: f(x) = sin(x) – 5
Answer:
The graph is shown below.
Step-by-step explanation:
The trigonometric expression is:
[tex]f(x)=sin\ (x)-5[/tex]
The general form is:
[tex]f(x)=a\ \text{sin}\ (bx-c)+d[/tex]
Comparing the two expression we know:
a = 1
b = 1
c = 0
d = -5
Compute the value of amplitude, |a | as follows:
[tex]\text{Amplitude}=|a|=|1|=1[/tex]
Compute the period of the function as follows:
[tex]\text{Period}=\frac{2\pi}{|b|}=\frac{2\pi}{|1|}=2\pi[/tex]
Compute the phase shift as follows:
[tex]\text{Phase Shift }=\frac{c}{b}=\frac{0}{1}=0[/tex]
The vertical shift is:
[tex]\text{Vertical Shift}=d=-5[/tex]
The properties of the trigonometric function are:
Amplitude = 1
Period = 2π
Phase shift = 0
Vertical shift = -5
Plot the graph of the trigonometric function by selecting a few points.
x : [tex]0[/tex] [tex]\frac{\pi}{2}[/tex] [tex]\pi[/tex] [tex]\frac{3\pi}{2}[/tex] [tex]2\pi[/tex]
f (x) : -5 -4 -5 -6 -5
The graph is shown below.
the cost of a leather coat went up from $75 to $90. what is the percent increase?
Answer:
20%
Step-by-step explanation:
The increase is ...
$90 -75 = $15
As a percentage of the original price, that is ...
$15/$75 × 100% = 0.20×100% = 20%
The increase was 20%.
Distribute and simplify these radicals. square root of 60
Answer:
2 sqrt(15)
Step-by-step explanation:
sqrt(60) = sqrt(4*15) = 2 sqrt(15)
A campaign strategist wants to determine whether demographic shifts have caused a drop in allegiance to the Uniformian Party in Bowie County. Historically, around 62% of the county's registered voters have supported the Uniformians. In a survey of 196 registered voters, 57% indicated that they would vote for the Uniformians in the next election. Assuming a confidence level of 95% and conducting a one-sided hypothesis test, which of the following should the strategist do?
a. Accept the hypothesis that the proportion of Uniformian voters has not changed.
b. Accept the hypothesis that the proportion of Uniformian voters has decreased.
c. Conclude that the proportion of Uniformian voters is now between 56% and 62%.
d. There is not enough evidence to support the hypothesis that the proportion of Uniformian voters has decreased.
Answer:
d. There is not enough evidence to support the hypothesis that the proportion of Uniformian voters has decreased.
Step-by-step explanation:
This is a hypothesis test for a proportion.
The claim is that there is a significant drop in allegiance to the Uniformian Party in Bowie County.
Then, the null and alternative hypothesis are:
[tex]H_0: \pi=0.62\\\\H_a:\pi<0.62[/tex]
The significance level is 0.05.
The sample has a size n=196.
The sample proportion is p=0.57.
The standard error of the proportion is:
[tex]\sigma_p=\sqrt{\dfrac{\pi(1-\pi)}{n}}=\sqrt{\dfrac{0.62*0.38}{196}}\\\\\\ \sigma_p=\sqrt{0.001202}=0.035[/tex]
Then, we can calculate the z-statistic as:
[tex]z=\dfrac{p-\pi+0.5/n}{\sigma_p}=\dfrac{0.57-0.62+0.5/196}{0.035}=\dfrac{-0.047}{0.035}=-1.369[/tex]
This test is a left-tailed test, so the P-value for this test is calculated as:
[tex]\text{P-value}=P(z<-1.369)=0.0855[/tex]
As the P-value (0.0855) is greater than the significance level (0.05), the effect is not significant.
The null hypothesis failed to be rejected.
There is not enough evidence to support the claim that there is a significant drop in allegiance to the Uniformian Party in Bowie County.
Solve 23 - Q >-3(2-6)
Answer:
q < 11
Step-by-step explanation:
Distribute the -3
23 - q > 12
Add q and subtract 12
q < 11
Step-by-step explanation:
the answer is
q<11
23-q>12
Isabella averages 152 points per bowling game with a standard deviation of 14.5 points. Suppose Isabella's points per bowling game are normally distributed. Let X= the number of points per bowling game. Then X∼N(152,14.5)______.
If necessary, round to three decimal places.
Suppose Isabella scores 187 points in the game on Sunday. The z-score when x=187 is ___ The mean is _________
This z-score tells you that x = 187 is _________ standard deviations.
Answer:
The z-score when x=187 is 2.41. The mean is 187. This z-score tells you that x = 187 is 2.41 standard deviations above the mean.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
In this question:
[tex]\mu = 152, \sigma = 14.5[/tex]
The z-score when x=187 is ...
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{187 - 152}{14.5}[/tex]
[tex]Z = 2.41[/tex]
The z-score when x=187 is 2.41. The mean is 187. This z-score tells you that x = 187 is 2.41 standard deviations above the mean.
The functions s and t are defined as follows. s(x)=3x-4 t(x)=-5x+3 Find the value of s(t(-1)).
t(x)=-5x+3
t(-1)=-5*(-1)+3=5+3=8
s(x)=3x-4
s(t(-1))=s(8)=3*8-4=24-4=20
answer is 20
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer:
its b I belive
Step-by-step explanation:
Answer:
The answer is B.
Step-by-step explanation:
In order to find (f-g)(x), you have to subtract g(x) from f(x) :
[tex]f(x) = {3}^{x} + 10[/tex]
[tex]g(x) = 2x - 4[/tex]
[tex](f - g)(x) = {3}^{x} + 10 - 2x - ( - 4)[/tex]
[tex](f - g)(x) = {3}^{x} + 10 - 2x + 4[/tex]
[tex](f - g)(x) = {3}^{x} - 2x + 14[/tex]
Pernyataan berikut yang benar adalah ....
A. Garis bagi membagi sisi menjadi dua sama panjang
B. Garis bagi membagi sudut menjadi dua sama besar
C. Garis berat membagi sudut menjadi dua sama besar
D. Garis tinggi membagi sudut menjadi dua sama besar
find the vector reciprocal to set. a= i+2j+2k, b= 2i+3j+k, c= i-j-2k
Answer:
I just do a' as a sample. You calculate b' and c'
Step-by-step explanation:
[tex]a'=\frac{b\times c}{a\bullet (b\times c)}, b' = \frac{c\times a}{a\bullet (b\times c)}, c' = \frac{a\times b}{a\bullet (b\times c)}[/tex]
Now, calculate b x c
[tex]\left[\begin{array}{ccc}i&j&k\\2&3&1\\1&-1&-2\end{array}\right] =<-5, 5,-5>[/tex]
[tex]a'=\frac{<-5,5,-5>}{<1, 2, 2>\bullet <-5, 5,-5>}=\frac{<-5, 5, -5>}{-5} =<1,-1,1>[/tex]
Which statements are true?
If all angles of a quadrilateral are right angles, then the quadrilateral must be a square.
Two shapes are similar if and only if their corresponding angles are equal.
All quadrilaterals have four sides, and the sum of all angles in a quadrilateral is 180º.
if the diagonals of a quadrilateral are perpendicular bisectors, then the quadrilateral must be a rhombus.
There are three vertices in a triangle, or there are four sides in a pentagon.
Any two triangles are either similar or congruent.
Answer:
Step-by-step explanation:
1) If all angles of a quadrilateral are right angles, then the quadrilateral must be a square. This is not true because the quadrilateral can also be a rectangle.
2) Two shapes are similar if and only if their corresponding angles are equal. This is true.
3) All quadrilaterals have four sides, and the sum of all angles in a quadrilateral is 180º. This is false because the sum of the angles is 360°
4) if the diagonals of a quadrilateral are perpendicular bisectors, then the quadrilateral must be a rhombus. This is true.
5) There are three vertices in a triangle, or there are four sides in a pentagon. This is false because a Pentagon has 5 sides.
6) Any two triangles are either similar or congruent. This is not true. Congruent triangles are always similar
Therefore, the true statements are 2 and 4
Answer:
its B and D
Step-by-step explanation:
Please help! Been stuck on this for hours Solve the inequality. Express your answer in interval form. (If there is no solution, enter NO SOLUTION.) 2 ≤ |x^2 − 4| < 4
Answer:
(-√8, -√6] ∪ [-√2, 0) ∪ (0, √2] ∪ [√6, √8)
Step-by-step explanation:
The inequality resolves into 4 inequalities. There are 4 intervals in the solution.
Starting at the left, for the absolute value argument less than 0:
2 ≤ -(x^2 -4) . . . . . . . for x^2 -4 ≤ 0
2 ≤ -x^2 +4
-2 ≤ -x^2
2 ≥ x^2 . . . . . . . . . . consistent with the above 4 ≥ x^2
-√2 ≤ x ≤ √2 . . . . . square root; may be limited by other constraints
For the absolute value argument greater than 0:
2 ≤ x^2 -4 . . . . . . . for x^2 -4 ≥ 0
6 ≤ x^2 . . . . . . . . . .consistent with x^2 ≥ 4
-√6 ≥ x ∪ x ≤ √6 . . . . take the square root
__
The inequality on the right can be written as the compound inequality ...
-4 < x^2 -4 < 4
0 < x^2 < 8 . . . . . add 4
0 < |x| < √8 . . . . take the square root
This resolves to ...
-√8 < x < 0 ∪ 0 < x < √8
__
So, the solution set is the set of values of x that satisfy these restrictions on x:
-√2 ≤ x ≤ √2
x ≤ -√6 ∪ x ≤ √6
-√8 < x < 0 ∪ 0 < x < √8
That is a collection of 4 intervals:
(-√8, -√6] ∪ [-√2, 0) ∪ (0, √2] ∪ [√6, √8)
_____
You may be expected to write √8 as 2√2.
__
These intervals are the portions of the red curve that lie between the two horizontal lines. The points on the upper (dashed) line are not part of the solution set. The points on the lower (solid) line are part of the solution set.
Which explains how to find the quotient of the division below? - 3 1/3 divided by 4/9 Write Negative 3 and one-third as Negative StartFraction 13 over 3 EndFraction, and find the reciprocal of StartFraction 4 over 9 EndFraction as StartFraction 9 over 4 EndFraction. Then, rewrite Negative 3 and one-third divided by StartFraction 4 over 9 EndFraction as Negative StartFraction 13 over 3 EndFraction times StartFraction 9 over 4 EndFraction. The quotient is Negative 9 and three-fourths. Write Negative 3 and one-third as Negative StartFraction 10 over 3 EndFraction, and find the reciprocal of StartFraction 4 over 9 EndFraction as StartFraction 9 over 4 EndFraction. Then, rewrite Negative 3 and one-third divided by StartFraction 4 over 9 EndFraction as Negative StartFraction 10 over 3 EndFraction times StartFraction 9 over 4 EndFraction. The quotient is Negative 7 and StartFraction 6 over 12 EndFraction = Negative 7 and one-half. Write Negative 3 and one-third as Negative StartFraction 9 over 3 EndFraction. Then, rewrite Negative 3 and one-third divided by StartFraction 4 over 9 EndFraction as Negative StartFraction 9 over 3 EndFraction times StartFraction 4 over 9 EndFraction. The quotient is Negative 1 and one-third. Write Negative 3 and one-third as Negative StartFraction 10 over 3 EndFraction. Then, rewrite Negative 3 and one-third divided by StartFraction 4 over 9 EndFraction as Negative StartFraction 10 over 3 EndFraction times StartFraction 4 over 9 EndFraction. The quotient is Negative 1 and StartFraction 13 over 27 EndFraction = Negative 1 and StartFraction 13 over 27 EndFraction
Answer:
The answer is D
Step-by-step explanation:
Answer:
A
Step-by-step explanation:
What is the vertex of f(x) = |x+ 8|– 3?
(-8, -3)
(-8,3)
(8, -3)
(8,3)
Answer:
The vertex is at (-8,-3)
Step-by-step explanation:
The function is of the form
y = a|x-h| + k where (h,k) is the vertex
f(x) = |x+ 8|– 3
f(x) = |x - - 8|– 3
The vertex is (-8,-3)
X and Y are both standard normal random variables (mean = 0, standard deviation = 1), statistically independent of each other. Using the DATA IN THE ATTACHED FILE, estimate the probability that X and Y are both positive and that their sum is less or equal to 1. This probability is
Answer:
The probability that X and Y are both positive and that their sum is less or equal to 1 0.64.
Step-by-step explanation:
It is provided that the random variables X and Y follows a standard normal distribution.
That is, [tex]X,Y\sim N(0, 1)[/tex]
It is also provided that the variables X and Y are statistically independent of each other.
Compute the probability that X and Y are both positive and that their sum is less or equal to 1 as follows:
The mean and standard deviation of X + Y are:
[tex]E(X+Y)=E(X)+E(Y)=0+0=0\\\\SD(X+Y)=\sqrt{V(X)+V(Y)+2Cov(X,Y)}=\sqrt{1+1+0}=\sqrt{2}[/tex]
The probability is:
[tex]P(X+Y\leq 1)=P(X+Y<1-0.50)\ [\text{Apply continuity correction}]\\[/tex]
[tex]=P(X+Y<0.50)\\\\=P(\frac{(X+Y)-E(X+Y)}{SD(X+Y)}<\frac{0.50-0}{\sqrt{2}})\\\\=P(Z<0.354)\\\\=0.63683\\\\\approx 0.64[/tex]
*Use the z-table.
Thus, the probability that X and Y are both positive and that their sum is less or equal to 1 0.64.
A rhombus is a quadrilateral with four congruent sides. The perimeter of rhombus WXYZ is less than 32 inches. Which inequality can be used to find all possible side lengths, s, for rhombus WXYZ? s squared greater-than 32 s squared less-than 32 4 s less-than 32 4 s greater-than 32
Answer:
4s< 32
Step-by-step explanation:
Congruent sides mean they are all the same length
Let the length be s
Perimeter means add the sides
s+s+s+s < 32
4s< 32
Answer:
4s>32
Step-by-step explanation:
your welcome dears
A soccer league has 180 players. Of those players 50% are boys. How many boys are in the soccer league?
Answer:
90 boys
Step-by-step explanation:
There are 180 players
Multiply by the percent that are boys to find the number of boys
180 * 50%
180 * .50
90
Answer:
90 boys
Step-by-step explanation:
The soccer league has 180 players, and 50% or half are boys.
Multiply the total number of players in the league by the percent that are boys.
total number of players * percent of boys
180* 50%
Convert 50% to a decimal by dividing by 100, or moving the decimal place 2 spaces to the left.
50/100=0.50
50.0–>5.0–>0.50
180*0.50
Multiply
90
There are 90 boy soccer players in the league.
What is the mode of this set of data?
Answer:
The mode is 15
Step-by-step explanation:
The mode is the number which appears most often in a set of numbers. Example: in {6, 3, 9, 6, 6, 5, 9, 3} the Mode is 6 (it occurs most often).
Answer:
The mode of this set is 15.
Step-by-step explanation:
the mode is 15 bcoz 15 is repeated two times where as other numbers aren't repeated..
which one of the following solids produces these two-dimensional shape when sliced horizontally?
Answer:
D
Step-by-step explanation:
Suppose you buy a CD for $500 that earns 3% APR and is compounded quarterly. The CD matures in 3 years. Assume that if funds are withdrawn before the CD matures, the early withdrawal fee is 3 months' interest. What is the early withdrawal fee on this account?
Answer:
$3.75
Step-by-step explanation:
I = Prt
I = $500·0.03·(3/12) = $3.75
The early-withdrawal fee is $3.75 for the first quarter.
_____
Each quarter after that, the principal amount will be larger, so the interest penalty will be larger. The fee would be the amount of interest that would be credited at the end of the next quarter, or at the end of the quarter currently in progress.
Help, please. I dont really understand
Answer:
We can eliminate the second and third options because marking something up doesn't result in a number less than the original. Since we are told to select 3 options and there are 3 answer choices left we select the first, fourth, and fifth statements.