Answer:
a. The researcher makes sure that the proportion of respondents from each state matches the proportion of each state's population to the US population.
b. The researcher gets the complete list from the Census Bureau and surveys every 1500th person on the list.
c. The researcher gets the complete list from the Census Bureau and uses a computer to randomly select 2000 people.
d. The researcher picks 20 different small groups:a church group a Democrat club a student club etc. each containing 100 people. Then the researcher makes sure that everyone from each group answers the survey question.
e. The researcher posts the survey on the Internet the survey question and waits until 2000 people have responded.
Step-by-step explanation:
Samples may be classified as:
Convenient: Sample drawn from a conveniently available pool.
Random: Basically, put all the options into a hat and drawn some of them.
Systematic: Every kth element is taken. For example, you want to survey something on the street, you interview every 5th person, for example.
Cluster: Divides population into groups, called clusters, and each element in the cluster is surveyed.
Stratified: Also divides the population into groups. However, then only some elements of the group are surveyed.
The researcher posts the survey on the Internet the survey question and waits until 2000 people have responded.
First 2000, so convenience.
The researcher gets the complete list from the Census Bureau and surveys every 1500th person on the list.
Every kth element, k = 1500, so systematic.
The researcher gets the complete list from the Census Bureau and uses a computer to randomly select 2000 people.
Randomly selects 2000 people, so random sampling.
The researcher makes sure that the proportion of respondents from each state matches the proportion of each state's population to the US population.
Divides the population into groups(by state), and a few members of each group are surveyed, so stratified.
The researcher picks 20 different small groups:a church group a Democrat club a student club etc. each containing 100 people. Then the researcher makes sure that everyone from each group answers the survey question.
Each element of the cluster is surveyed, so cluster sampling.
In ATUV, the measure of _V=90°, VU = 84, TV = 13, and UT = 85. What ratio
represents the cotangent of _T?
U
85
84
T
13
A journal article reports that 34% of fathers take no responsibility for child care. A group of fathers believes that this estimate is too high. In a random sample of 80 fathers, it was found that 23 of those fathers take no responsibility for child care. Is there significant evidence at the 1% significance level that less than 34% of fathers take no responsibility for child care
Answer:
The p-value of the test is 0.1611>0.01, which means that there is not significant evidence at the 1% significance level that less than 34% of fathers take no responsibility for child care
Step-by-step explanation:
A journal article reports that 34% of fathers take no responsibility for child care. A group of fathers believes that this estimate is too high.
At the null hypothesis, we test if the proportion is of at least 34%, that is:
[tex]H_0: p \geq 0.34[/tex]
At the alternative hypothesis, we test if the proportion is less than that, that is:
[tex]H_1: p < 0.34[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
0.34 is tested at the null hypothesis:
This means that [tex]\mu = 0.34, \sigma = \sqrt{0.34*0.66}[/tex]
In a random sample of 80 fathers, it was found that 23 of those fathers take no responsibility for child care.
This means that [tex]n = 80, X = \frac{23}{80} = 0.2875[/tex]
Value of the test statistic:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{0.2875 - 0.34}{\frac{\sqrt{0.34*0.66}}{\sqrt{80}}}[/tex]
[tex]Z = -0.99[/tex]
P-value of the test and decision:
The p-value of the test is the probability of finding a sample proportion below 0.2875, which is the p-value of Z = -0.99.
Looking at the Z-table, Z = -0.99 has a p-value of 0.1611.
The p-value of the test is 0.1611>0.01, which means that there is not significant evidence at the 1% significance level that less than 34% of fathers take no responsibility for child care
What is an opposite number?
Answer:
The opposite of a number is the number on the other side of 0 number line, and the same distance from 0.
A triangular prism has a base area of 12 square centimeters, and a height of 15 centimeters. What is the volume?
A point particle with charge q is at the center of a Gaussian surface in the form of a cube. The electric flux through any one face of the cube is: _________.
i. q/E0
ii. q/E4Ï€E0
iii. q/4E0
iv. q/6E0
v. q/16E0
Answer:
iv. q/6E0
Step-by-step explanation:
Electric flux formula:
The electic flux formula, of a charge q is given by, through an entire cube, is given by:
[tex]E = \frac{q}{E_o}[/tex]
In which [tex]E_o[/tex] is a constant related to the material.
The electric flux through any one face of the cube is:
Key-word is face, and a cube has 6 faces, with the force distributed evenly throughout it. Thus
[tex]E_f = \frac{1}{6} \times \frac{q}{E_o} = \frac{q}{6E_o}[/tex]
And the correct answer is given by option iv.
Assume the random variable X is normally distributed with mean μ = 50 and standard deviation σ= 7. Compute the probability.
Complete question is;
Assume the random variable X is normally distributed with mean μ = 50 and standard deviation σ = 7. What is the probability P (X > 42)?
Answer:
P(X > 42) = 0.1271
Step-by-step explanation:
We are given;
mean; μ = 50
Standard deviation; σ = 7
Formula for the z-score is;
z = (x - μ)/σ
Thus;
z = (42 - 50)/7
z = -1.14
Since we are looking for P (X > 42), then let's look up this z-value from the z-distribution table attached.
We have;
P(X > 42) = 0.1271
A company's mean salary is $65,000 with a standard deviation of $6,000. If a sample of
40 employees is taken, determine the standard error.
948.68
325.25
9328.71
none of these
Answer:
umm not sure on this one either 9328.71
Step-by-step explanation:
Can you help me please
Answer:
no solution
Step-by-step explanation:
[tex]\dfrac{2x - 6}{4} > \dfrac{x - 3}{2}[/tex]
The LCD is 4, so multiply both sides of the inequality by 4.
[tex]4 \times \dfrac{2x - 6}{4} > 4 \times \dfrac{x - 3}{2}[/tex]
[tex]2x - 6 > 2 \times (x - 3)[/tex]
[tex]2x - 6 > 2x - 6[/tex]
Subtract 2x from both sides.
[tex]-6 > -6[/tex]
Since -6 = -6, the above statement is false, so there are no solutions.
Answer: no solution
What the mass of Earth's water?
Answer:
The total mass of Earth's hydrosphere is about 1.4 × 1018 tonnes, which is about 0.023% of Earth's total mass. At any given time, about 20 × 1012 tonnes of this is in the form of water vapor in the Earth's atmosphere (for practical purposes, 1 cubic meter of water weighs one tonne).
Step-by-step explanation:
A balloon is 4 ft above the ground. It is released and floats up 3 ft
every second. Write an equation to model the height of the balloon
as a function of time in seconds. Write your answers in the blanks.
Answer:
4+(3 times x)= height of balloon. x = seconds
Step-by-step explanation:
I hope this helps you! :D
A stadium's normal ticket price is $78. As a special promotion they offer 15% off. What is the price of the discounted
ticket?
Answer:
$66.3
Step-by-step explanation:
price of a ticket without discount = $78
discount % = 15%
discount amount = ?
price of a discounted ticket = ?
discount amount = discount% of price of a original ticket
=15/100 * $78
=$1170/100
=$ 11.7
price of the discounted ticket = $78 - $11.7
=$66.3
The discounted price of the stadium's normal ticket is $66.3
What is the percentage?A percentage is a value per hundredth. Percentages can be converted into decimals and fractions by dividing the percentage value by a hundred.
Given, A stadium's normal ticket price is $78 and As a special promotion they offer 15% off.
Therefore, The discounted price of the ticket should be (100 - 15)% = 85% of the original price which is,
= (85/100)×78.
= $66.3 is the discounted price.
learn more about percentages here :
https://brainly.com/question/24159063
#SPJ6
Which system of equations represents the matrix shown below?
Answer:
c
Step-by-step explanation:
I need help with this question I wanna say the answers B
Answer:
hi, yes the option B is the correct answer
Ordena de mayor a menor el siguiente grupo de fracciones y decimales
-2,14; 7/50; -2,41; -11/8; -2,1
Answer:
-2.41: -2.14: -2.1: -11/8: 7/50
How many 3/4 inch strips for caulk to cover 10 1/2 inches
Answer:
14
Step-by-step explanation:
So let's think smart. If you look at the image I made a diagram. The 3 squares I colored in represent 3/4. It takes 14 3/4 strips to cover 10 1/2 inches.
The Number of 3/4 inch strips required to cover 10 1/2 inches of caulk will be 14
The total inches of caulk to be covered = 10 1/2 inches
The fraction of inch strip to be used = 3/4 inches
To obtain the number of 3/4 inch strop required ;
We divide the total inches of caulk by 3/4
Hence,
10 1/2 ÷ 3/4
21/2 ÷ 3/4
Change the sign to × and take the reciprocal of 3/4 ;
21/2 × 4/3
(21 × 4) / (2 × 3) = 84 / 6
84 / 6 = 14
Hence, the number of 3/4 inch strip required is 14
Learn more : https://brainly.com/question/2610134
20 points probability question
Answer:
a. n^2-2n+1/n squared
b. 9 green counters
Step-by-step explanation:
just as you role 3 dices and the chances are MULTIPLIED, the same goes for this problem.
n-1/n times n-1/n would create the probability of getting 2 green counters randomly from the bag's possibility.
n-1/n times n-1/n can be said as (n-1) squared or in simple terms:
n^2 -2n+1 or in words, n squared -2n +1.
divided by n squared is the fraction probability in simplest form:
n^2-2n+1/n squared
the next question is actually much easier:
0.9 is 90% in percentages, this can be detrimental to your grade if your teachers asked you for the decimal, not percentage of it.
for 1 every yellow counter, there is 9 green counters. so in the bag, there is one yellow counter meaning there are 9 green counters in the bag (after finishing the first question)
Part (a)
Answer: (n-2)/n----------------
Explanation:
There are n-1 green counters to start out of n counters total.
The probability of selecting a green counter is (n-1)/n
The probability of selecting a second green counter is (n-2)/(n-1) since we're not putting the first counter back.
Multiplying the two fractions leads to (n-2)/n
Note how the (n-1) terms cancel.
===============================================================
Part (b)
Answer: 19 green counters----------------
Explanation:
We set the result of part (a) equal to 0.9 and solve for n
(n-2)/n = 0.9
(n-2)/n = 9/10
10(n-2) = 9n ... cross multiply
10n-20 = 9n
10n-9n = 20
n = 20
We have 20 counters in the bag. One counter is yellow and the remaining n-1 = 20-1 = 19 are green.
The probability of getting one green counter is 19/20
The probability of a second green counter is 18/19
The probability of two green counters is (19/20)*(18/19) = 18/20 = 9/10 = 0.9
This helps confirm the answer.
Need help practice problem please
Answer:
I think there is no solution.
Step-by-step explanation:
Substitute:
Z = -3y-5x+25
X = 3y-2z-13
Put into the last formula:
14(3y-2z-13)-2y+3(-3y-5x+25) = 48
Then:
14(3y-2(-3y-5x+25)-13)-2y+3(-3y-5(3y-2z-13)) = 48
So:
14(3y-2(-3y-5(3y-2z-13)+25)-13)-2y+3(-3y-5(3y-2(-3y-5x+25)-13)) = 48
And so on.
Find the equation of a line perpendicular to x+5y=−2 that contains the point (3,0).
Perpendicular Definition:
[tex] \large \boxed{m_1m_2 = - 1}[/tex]
Slopes of two different equations multiply each others and must equal to -1. We can also say that the perpendicular occurs only if both equations are negative reciprocal to each others. For example, we are given the equation of y = 2x. The perpendicular to y = 2x would be y = (-1/2)x. See how both are reciprocal to each others.
From the equation below:
[tex] \large{x + 5y = - 2}[/tex]
Since the equation is in the form of Ax+By = C. It is better to use the another slope formula which is:
[tex] \large \boxed{m = - \frac{A}{B} }[/tex]
From the equation above, use the slope formula to find the slope.
[tex] \large{m = - \frac{1}{5} }[/tex]
Therefore the equation has a slope of -1/5. Next to find the perpendicular equation to the original equation. Since our slope is -1/5 - that means the negative reciprocal of -1/5 is 5. Therefore the slope of perpendicular line is 5.
Next we will be using the point-slope form below:
[tex] \large \boxed{y - y_1 = m(x - x_1)}[/tex]
Given the y1 and x1 or (x1,y1) are the points. Our perpendicular slope is 5 which passes through the point (3,0). Substitute both slope and the point in.
[tex] \large{y - 0 = 5(x - 3)}[/tex]
Simplify in the slope-intercept form as we get:
[tex] \large{y = 5x - 15}[/tex]
Answer
y = 5x-15 is perpendicular to x+5y = -2Hope this helps and let me know if you have any doubts!
mike is looking at the roof of a new house from the front. he notices that the roof is triangular in shape with a base 11.2m. the left side is 6.7m long and makes an angle of 72 degree with the base of the roof. if this is the only known information, determine the angle the right side of the roof makes with the base of the roof to the nearest degree. be sure to first make a sketch
Answer:
35°
Step-by-step explanation:
From the sketch made, to obtain B we use the cosine angle formula :
We have 2 so des and an included angle
Cos B = (a² + c² - b²) / 2ac
First we obtain the side c
c² = a² + b² - 2ab CosC
c² = 11.2² + 6.7² - 2(11.7 * 6.7) * cos 72
c = 11.13
Using the value of c
Cos B = (a² + c² - b²) / 2ac
CosB = (11.2² + 11.13² - 6.7²) / (2*11.2*11.13)
Cos B = 204.4269 / 249.312
B = Cos^-1(204.4269 / 249.312)
B = 34.9°
2. The set {0,1,-1} is closed under the operation of?
When do creative people get their best ideas? USA Today did a survey of 966 inventors (who hold U.S. patents) and obtained the following information.
Time of Day When Best Ideas Occur
Time Number of Inventors
6 A.M.-12 noon
12 noon-6 P.M.
6 P.M.-12 midnight
12 midnight-6 A.M. 295
138
311
222
Assuming that the time interval includes the left limit and all the times up to but not including the right limit, estimate the probability that an inventor has a best idea during each time interval: from 6 A.M. to 12 noon, from 12 noon to 6 P.M., from 6 P.M. to 12 midnight, from 12 midnight to 6 A.M. (Enter your answers to 3 decimal places.)
6AM-12PM 12PM-6PM 6PM-12AM 12AM-6AM
Answer:
[tex]P(6am-12\ noon) = 0.305[/tex]
[tex]P(12\ noon - 6pm) = 0.143[/tex]
[tex]P(6pm-12\ midnight) = 0.322[/tex]
[tex]P(12\ midnight - 6am) =0.230[/tex]
Step-by-step explanation:
Given
[tex]\begin{array}{cc}{Time} & {Inventors} & {6am - 12\ noon} & {295} & {12\ noon -6pm} & {138} & {6pm - 12\ midnight} & {311} & {12\ midnight - 6am} & {222} & {Total} & {966} \ \end{array}[/tex]
Required
The probability of each time interval
To do this, we simply divide the number of inventors in the interval by the total inventors (966)
So, we have:
[tex]P(6am-12\ noon) = \frac{6am-12\ noon}{Total}[/tex]
[tex]P(6am-12\ noon) = \frac{295}{966}[/tex]
[tex]P(6am-12\ noon) = 0.305[/tex]
[tex]P(12\ noon - 6pm) = \frac{12\ noon - 6pm}{Total}[/tex]
[tex]P(12\ noon - 6pm) = \frac{138}{966}[/tex]
[tex]P(12\ noon - 6pm) = 0.143[/tex]
[tex]P(6pm-12\ midnight) = \frac{6pm-12\ midnight}{Total}[/tex]
[tex]P(6pm-12\ midnight) = \frac{311}{966}[/tex]
[tex]P(6pm-12\ midnight) = 0.322[/tex]
[tex]P(12\ midnight - 6am) =\frac{12\ midnight - 6am}{Total}[/tex]
[tex]P(12\ midnight - 6am) =\frac{222}{966}[/tex]
[tex]P(12\ midnight - 6am) =0.230[/tex]
HELPPPPPPPPPPPPPPPPPPPP
Answer:
b.
Step-by-step explanation:
c= 3r
such that 3(6) = 18 ...
Hakim is making birdhouses. Each birdhouse uses 78 yard of wood.
What is the total length of wood Hakim will need to build 5 birdhouses?
A. 438 yards
B. 578 yards
C. 148 yards
D. 928 yards
Answer:
390 yds
Step-by-step explanation:
Take the amount of wood per birdhouse and multiply by the number of birdhouses being made
78 * 5 =390 yds
Answer:
390 yds
Step-by-step explanation:
Take the amount of wood per birdhouse and multiply by the number of birdhouses being made
78 * 5 =390 yds
Hope this helps!!!
elimination was used to solve a system of equations. one of the intermediate steps led to the equation 2x= 8. which of the following systems could have led to this equation?
9514 1404 393
Answer:
C
Step-by-step explanation:
The step shown indicates that y was eliminated from the equations. For choices A, B, D, this is done by adding the equations together (the y-coefficients are opposites). The result of doing that gives x-terms of 4x, 0x, and 0x, respectively. These x-terms do not match the one given: 2x.
For choice C, the y-term is eliminated by subtracting twice the second equation from the first. Doing that gives ...
(4x +2y) -2(x +y) = (14) -2(3)
4x +2y -2x -2y = 14 -6 . . . . eliminate parentheses
2x = 8 . . . . . . . . . . . . . . collect terms
Find the median and mean of the data set below:
10, 43, 20, 11
What's 3 times 4/5 as a improper fraction
What is the result of a dilation of scale factor 3 centered at the origin of the line 2y + 3x=10?? PLEASE HELP PLEASEEEEEEEEE
Given:
The equation of a line is:
[tex]2y+3x=10[/tex]
The line is dilated by factor 3.
To find:
The result of dilation.
Solution:
The equation of a line is:
[tex]2y+3x=10[/tex]
For [tex]x=0[/tex],
[tex]2y+3(0)=10[/tex]
[tex]2y+0=10[/tex]
[tex]y=\dfrac{10}{2}[/tex]
[tex]y=5[/tex]
For [tex]x=2[/tex],
[tex]2y+3(2)=10[/tex]
[tex]2y+6=10[/tex]
[tex]2y=10-6[/tex]
[tex]2y=4[/tex]
Divide both sides by 2.
[tex]y=\dfrac{4}{2}[/tex]
[tex]y=2[/tex]
The given line passes through the two points A(0,5) and B(2,2).
If the line dilated by factor 3 with origin as center of dilation, then
[tex](x,y)\to (3x,3y)[/tex]
Using this rule, we get
[tex]A(0,5)\to A'(3(0),3(5))[/tex]
[tex]A(0,5)\to A'(0,15)[/tex]
Similarly,
[tex]B(2,2)\to B'(3(2),3(2))[/tex]
[tex]B(2,2)\to B'(6,6)[/tex]
The dilated line passes through the points A'(0,15) and B'(6,6). So, the equation of dilated line is:
[tex]y-y_1=\dfrac{y_2-y_1}{x_2-x_1}(x-x_1)[/tex]
[tex]y-15=\dfrac{6-15}{6-0}(x-0)[/tex]
[tex]y-15=\dfrac{-9}{6}(x)[/tex]
[tex]y-15=\dfrac{-3}{2}x[/tex]
Multiply both sides by 2.
[tex]2(y-15)=-3x[/tex]
[tex]2y-30=-3x[/tex]
[tex]2y+3x=30[/tex]
Therefore, the equation of the line after the dilation is [tex]2y+3x=30[/tex].
Shine has some money in his account.Every Month, he used the same amount of money from his account to pay for his music classes. The table below shows the amount of money left in his account after a certain amount of time, in months:
Option 4) -$45 per month; the amount of money withdrawn per month
Answer:
Option 4) -$45 per month; the amount of money withdrawn per month.
Step-by-step explanation:
The rate of change is 45. Before he began taking money out to pay for his classes[month 0], he had $190. Since then, every month, $45 have been withdrawn.
2) What is the probability you roll an odd number on a six-
sided die ?
Answer:
1/2 or 0.5
Step-by-step explanation:
All possible odd values on a 6-sided die include 1, 3, and 5; that is 3 values out of 6 total values. 3/6 or 1/2 is a 0.5 probability.
Find Use proportion
24 =18/15
21
b
18
20
16
Answer:
Step-by-step explanation:
