Answer:
1. Option c
2. Option d
Step-by-step explanation:
This type of survey is includes a sample made up of voluntary responses. People only choose to or do not choose to respond.
This type of sampling method is most of the time unbelievable because generally only people with strong opinions about this particular questions will respond and it is usually towards the same direction as the question and this might not reflect the opinion of the whole population making the survey biased.
Part A: The respondents are a voluntary response sample (Option C)
Part B: Responses may not reflect the opinions of the general population (Option D)
The total number of internet users = 1072
Percentage of the total number of people that chose to respond = 38%
Note that this survey does not compel all the population to respond to the survey. Responses are gotten from voluntary respondents.
Also note that a voluntary response sample is a sample that consists of participants who chose to participate in a sample group voluntarily.
In this type of survey, the people who decided to provide voluntary responses to the survey are called voluntary response samples
The percentage of those that chose to respond to this survey (38%) is less than half of the total population. This obviously shows that the responses may not reflect the opinions of the general population
Learn more on sampling methods here: https://brainly.com/question/16587013
A recent survey found that 86% of employees plan to devote at least some work time to follow games during the NCAA Men's Basketball Tournament. A random sample of 100 employees was selected. What is the probability that less than 80% of this sample will devote work time to follow games?
Answer:
4.18% probability that less than 80% of this sample will devote work time to follow games
Step-by-step explanation:
Normal probability distribution
When the distribution is normal, we use 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.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
In this question, we have that:
[tex]p = 0.86, n = 100[/tex]
So
[tex]\mu = 0.86, s = \sqrt{\frac{0.86*0.14}{100}} = 0.0347[/tex]
What is the probability that less than 80% of this sample will devote work time to follow games?
This is the pvalue of Z when X = 0.8. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.8 - 0.86}{0.0347}[/tex]
[tex]Z = -1.73[/tex]
[tex]Z = -1.73[/tex] has a pvalue of 0.0418
4.18% probability that less than 80% of this sample will devote work time to follow games
Help me solve (b) in this quadrilateral
Answer:
b = 87°
Step-by-step explanation:
In order to answer this question, we need to utilise an important angle fact which is angles in a quadrilateral add up to 360°
Using the information we can set up an equation to find the value of b
→ Form equation
63 + 140 + 70 + b = 360
→ Simplify
273 + b = 360
→ Minus 273 from both sides isolate b
b = 87°
Answer:
Hello!
The answer is 87 degrees!
I hope I was of help! If not please let me know! Thank you!
Step-by-step explanation:
which of the following represents a function
Answer:
Second option
Step-by-step explanation:
For a set to represent a function, each input value in the set domain should match with one and only one output value of set range.
The option that follows this rule os second option as 1 is matched with 2 only, and 3 is matched with 3 only, and 5 is matched with 7 only.
Sidney made $35 less than four times Casey’s weekly salary. If x represents Casey’s weekly salary, write an expression for Sidney’s weekly salary.
Answer: [tex]y=4x-35[/tex]
y = Sidney’s weekly salary
x = Casey’s weekly salary
Answer: y=4x-35
x is Casey's salary
Y is Sidney's salary
Step-by-step explanation:
Sidney makes a quarter of Casey,
y=4x,
Then it also states that he makes 35 less than the first equation.
Therefore,
Y=4x-35
Create an explicit formula for the following sequence 1/3,-1,3,-9
Answer:
multiply by -3
Step-by-step explanation:
1/3 gives -3/3=-1
-1*-3=3
3*-3=-9
it defines the function f so that f(x)=-3x
Jack buys a bag of 5 apples, each
equal in size. He eats of 1/2 of one apple.
What fraction of the bag of
apples did he eat?
Answer:
4 1/2
Step-by-step explanation:
5 apples - 1/2 apple =
4 1/2 apple
or
9/2
10. You just hung a picture twelve inches above the wall trim. Your friend thinks the picture looks
crooked. Use what you know about parallel lines and transversals to determine if the picture is level.
Step 1: You don't have a level, but you are in luck. You know the wall trim is level. You have a
protractor and the sun is casting a shadow on the wall. Describe how you can determine if the picture
is level. (3 points)
Answer:
The angles measured between the shadow and the wall trim and the shadow and the top or bottom of the picture should be equal if the picture is level
Step-by-step explanation:
Whereby the picture is 12 inches above the wall trim and the Sun is casting a shadow on the wall, therefore, the edges of the shadow of a straight edged object is straight
If the picture is level, the shadow cast by the sun is transversal to the wall trim and the line formed by extending the bottom or top of the picture in the direction of the shadow. That is, if the picture is parallel, the shadow cast by the Sun on the wall is transversal to the picture and the wall trim if or when the shadow eventually crosses the picture
With the protractor, the angle between the shadow and the wall trim and the shadow and the top or bottom is measured
The angles measured should be the same if the picture is level.
Please answer this correctly
Answer:
d = 2
the diagonals are the different lengths
Step-by-step explanation:
What’s the correct answer for this?
Answer:
B.
Step-by-step explanation:
Since two diameters are intersecting eachother, the angles inside them would be vertical angles so they'll be congruent.
So
m<LYM = m<JYM
Also their arcs would be equal to their angles measures so,
Arc JK = 52°
Bernard bought 8gal of paint. Convert the volume to liters. Round to the nearest tenth
Answer:
In one gallon of paint there are about 3.8 liters so 8 gallons is about 30.3 liters.
Barron's reported that the average number of weeks an individual is unemployed is 18.5 weeks. Assume that for the population of all unemployed individuals the population mean length of unemployment is 18.5 weeks and that the population standard deviation is 6 weeks. Suppose you would like to select a sample of 55 unemployed individuals for a follow-up study.
A) show the sampling distribution of x, the sample mean average for a sample of 50 unemployment individuals.B) What is the probability that a simple random sample of 50 unemployment individuals will provide a sample mean within one week of the population mean?C) What is the probability that a simple random sample of 50 unemployed individuals will provide a sample mean within a half week of the population mean?
Answer:
A) The sampling distribution for a sample size n=50 has a mean of 18.5 weeks and a standard deviation of 0.849.
B) P = 0.7616
C) P = 0.4441
Step-by-step explanation:
We assume that for the population of all unemployed individuals the population mean length of unemployment is 18.5 weeks and that the population standard deviation is 6 weeks.
A) We take a sample of size n=50.
The mean of the sampling distribution is equal to the population mean:
[tex]\mu_s=\mu=18.5[/tex]
The standard deviation of the sampling distribution is:
[tex]\sigma_s=\dfrac{\sigma}{\sqrt{n}}=\dfrac{6}{\sqrt{50}}=0.849[/tex]
B) We have to calculate the probability that the sampling distribution gives a value between one week from the mean. That is between 17.5 and 19.5 weeks.
We can calculate this with the z-scores:
[tex]z_1=\dfrac{X_1-\mu}{\sigma/\sqrt{n}}=\dfrac{17.5-18.5}{6/\sqrt{50}}=\dfrac{-1}{0.8485}=-1.179\\\\\\z_2=\dfrac{X_2-\mu}{\sigma/\sqrt{n}}=\dfrac{19.5-18.5}{6/\sqrt{50}}=\dfrac{1}{0.8485}=1.179[/tex]
The probability it then:
[tex]P(|X_s-\mu_s|<1)=P(|z|<1.179)=0.7616[/tex]
C) For half a week (between 18 and 19 weeks), we recalculate the z-scores and the probabilities:
[tex]z=\dfrac{X-\mu}{\sigma/\sqrt{n}}=\dfrac{18-18.5}{6/\sqrt{50}}=\dfrac{-0.5}{0.8485}=-0.589[/tex]
[tex]P(|X_s-\mu_s|<0.5)=P(|z|<0.589)=0.4441[/tex]
Solve x for the diagram below.
Answer:
20°
Step-by-step explanation:
These angles add up to 90° so we have:
x + 2x + x + 10 = 90
4x + 10 = 90
4x = 80
x = 20°
Please answer this correctly
Answer:
A = 1/2 b*h
A = 24
b = 8
h = ?
24 = 1/2 * 8 * h
24 = 4h
h = 6
The height is 6 cm.
Hope this helps.
a)i.Write the the absolute value function y=|2x+5|+3|x-1| as a piece-wise function.
ii)What is the range?
Answer:
Step-by-step explanation:
for |2x+5|=
[tex]\left \{ {{2x+5}~~~~if~~~~2x+5 > 0 ~~or ~~~~x>\frac{-5}{2}~~(case 1) \\ \atop {-2x-5}} ~~~~~if~~~2x+5 <0 ~~~~or~~~x<\frac{-5}{2}~~(case 2)[/tex]
for |x-1| = [tex]\left \{ {{x-1 } ~~~~if~~~x-1>0 ~~~or~~~x>1 ~~(case 3)\atop {1-x}} ~~~~if ~~~~x-1<0 ~~~~or~~~x<1 \right. (case 4)[/tex]
Please help me with this problem I'm lost
Answer:
24
Step-by-step explanation:
Multiple (4)(2)= 8
-3(8) =24
Which expession is equivalent to -3(6c + 2) + 5c
Answer:
-13c-6
Step-by-step explanation:
-3(6c + 2) + 5c
Distribute
-18c -6 +5c
Combine like terms
-13c-6
Answer:
-13c -6
Step-by-step explanation:
-3 (6c) -3x2+5c
multiply 6 by -3
-18c-3x2+5c
multiply -3 by 2
-18c -6+ 5c
add 18c and 5c
-13c -6
Determine the maximum r-value of the polar equation r = 3 + 3 cos theta
Answer:
Step-by-step explanation:
6
which of the following expressions is equal to -3x^2-12??!!! please help him
Answer:
-3 ( x+2i) (x-2i)
Step-by-step explanation:
-3x^2-12
Factor out a -3
-3(x^2 +4)
Rewrite
-3 ( x^2 - -4)
-3 ( x^2 - (-2i)^2) This is the difference of squares ( a^2 -b^2 ) = (a-b)(a+b)
-3 ( x- -2i) (x+2i)
-3( x+2i) (x-2i)
Find the m∠YAX in the figure below
Answer:
76
Step-by-step explanation:
The two angles are vertical angles so they are equal
3x+7 = 4x-16
Subtract 3x from each side
3x-3x+7 = 4x-3x-16
7 = x-16
Add 16 to each side
7+16 = x-16+16
23 =x
We want YAX
YAX = 3x+7
3*23+7
69+7
76
Consider the following dice game, as played at a certain gambling casino: players 1 and 2 roll a pair of dice in turn. the bank then rolls the dice to determine the outcome according to the following rule: player i,i=1,2, wins if his roll is strictly
Ii={1 if i wins, 0 otherwise}
and show that I1 and I2 are positively correlated. Explain why this result was to be expected.
Answer:
they are positively correlated.
Step-by-step explanation:
We can calculate the individal expectations first. FIrst player will win if that player's roll is greater than the bank's roll. There are (6 possible rolls of player 1 * 6 possible rolls of bank =) 36 total possible rolls, out of which player 1 will win in 15 cases.
[tex]\therefore E(I_i) = 1\cdot \frac{15}{36} + 0 \cdot \frac{21}{36} = \frac{5}{12} \approx 0.4167[/tex]
For the joint expectation, there are (6 possible rolls of player 1 * 6 possible rolls of player 2 * 6 possible rolls of bank =) 216 total possible rolls.
Cases where both players win: Expectation = $2.
If bank rolls 1, both players will win in 5*5 = 25 cases. P1 is one of {2,3,4,5,6}, P2 is one of {2,3,4,5,6}
If bank rolls 2, both players will win in 4*4 = 16 cases.
If bank rolls 3, both players will win in 3*3 = 9 cases.
If bank rolls 4, both players will win in 2*2 = 4 cases.
If bank rolls 5, both players will win in 1*1 = 1 cases.
If bank rolls 6, both players will win in 0*0 = 0 cases.
Total cases = 25+16+9+4+1+0 = 55 cases.
Cases where player 1 wins $1 and player 2 loses: Expectation = $1.
If bank rolls 1, player 1 will win and player 2 will lose in 5*1 = 5 cases. P1 is one of {2,3,4,5,6}, P2 is {1}
If bank rolls 2, player 1 will win and player 2 will lose in 4*2 = 8 cases.
If bank rolls 3, player 1 will win and player 2 will lose in 3*3 = 9 cases.
If bank rolls 4, player 1 will win and player 2 will lose in 2*4 = 8 cases.
If bank rolls 5, player 1 will win and player 2 will lose in 1*5 = 5 cases.
If bank rolls 6, player 1 will win and player 2 will lose in 0*6 = 0 cases.
Total cases = 5+8+9+8+5+0 = 35
Cases where player 2 wins $1 and player 1 loses: Expectation = $1.
This is the same as above with player 1 and 2 exchanged.
Total cases = 35
Cases where both players lose: Expectation = $0.
If bank rolls 1, both players will lose in 1*1 = 1 cases. P1 is {1}, P2 is {1}
If bank rolls 2, both players will lose in 2*2 = 4 cases.
If bank rolls 3, both players will lose in 3*3 = 9 cases.
If bank rolls 4, both players will lose in 4*4 = 16 cases.
If bank rolls 5, both players will lose in 5*5 = 25 cases.
If bank rolls 6, both players will lose in 6*6 = 36 cases.
Total cases = 1+4+9+16+25+36 = 91 cases.
Total of all cases (we expect this to be 216 as mentioned above) = 55+35+35+91=216
So, joint expectation is:
[tex]E(I_1I_2) = \frac{2\cdot 55 +1\cdot 35+1\cdot 35+0\cdot 91}{216} = \frac{180}{216}= \frac{5}{6} \approx 0.8333[/tex]
So, the covariance is given by:
[tex]\texttt{Cov}(I_1I_2) =E(I_1I_2) -E(I_1)\cdot E(I_2)= \frac{5}{6}-\frac{5}{12}\cdot\frac{5}{12}=\frac{95}{144} \approx 0.6597[/tex]
As this is greater than 0 and closer to 1, they are positively correlated.
The reason why this result is expected is because the same bank roll is being used for both players. So, it is very likely that both players will win if the bank roll is 1 or even 2. Also, it is very likely that both players will lose if the bank roll is 6, 5, or even 4. This shows positive correlation between the events.
Find the first 4 terms and the 10th one n+5
Answer: First 4 terms of n + 5 = 6,7,8,9
10th term = 15
Hope this is right
Step-by-step explanation:
By putting n = 1 , 2, 3 , 4 we can find first 4 terms
When n = 1
n + 5 = 1 + 5 = 6
When n = 2
n + 5 = 2 + 5 = 7
When n = 3
n + 5 = 3 + 5 = 8
When n = 4
n + 5 = 4 + 5 = 9
When n = 10
n + 5 = 10 +5 = 15
Submit A political scientist wants to conduct a research study on a president's approval rating. The researcher has obtained data that states that 45% of citizens are in favor of the president. The researcher wants to determine the probability that 6 out of the next 8 individuals in his community are in favor of the president. What is the binomial coefficient of this study? Write the answer as a number, like this: 42.
Answer: 28
Step-by-step explanation: Im taking the same class here is a photo of the work, divide 56/2 than you get 28
Please help! Correct answer only, please! The following information matrices shows how many of each vehicle type sold and the bonus amount each salesperson receives for selling that type of vehicle for the car dealership for the week. What does the element LaTeX: A_{2,3}A 2 , 3represent? A. Mark sold 2 vans B. Scott sold 1 Van C. Mark sold 4 trucks D. Kelly sold 2 trucks
Answer: B) Scott sold 1 van
Step-by-step explanation:
A₂,₃ represents: matrix A - 2nd row - 3rd column
The second row is Scott and and the 3rd row is Vans
If you look at Scott - Vans, you will see that Scott sold 1 van.
What is the product of (n -8)(n + 2)?
n2 - 10n - 16
n2 + 10n - 16
n2 - On - 16
in 2 + 6n - 16
Answer:
n2-6n-16
Step-by-step explanation:
n(n+2)-8(n+2)
n2+2n-8n-16=
n2-6n-16
Answer: n 2 + 6n - 16
Step-by-step explanation:
Please everyone help me!
Answer:g=0 is not the solution
Step-byd-step explanation:
-1 1/2 is a negative number and 0 is not negative
Answer:
g=0
Step-by-step explanation:
happy to help ya :)
Classify the following triangle .check all that apply
Answer:
Isosceles right triangle
Answer:
It is a scalene triangle because 2 angles are equal and one angle is different .
Step-by-step explanation:
please mark as brainliest and follow me!!!!!...
A digital scale measures weight to the nearest 0.2 pound. Which measurements shows an appropriate level for the scale ?
Answer: Answer choices 1, 3, 4
Step-by-step explanation:
As long as it ends in .0, .2, .4, .6, or .8 it's fine. Therefore the first and last 2 work, since 0.2 can end in either of those 5 values.
Hope that helped,
-sirswagger21
Lightbulbs of a certain type are advertised as having an average lifetime of 750 hours. The price of these bulbs is very favorable, so a potential customer has decided to move forward with a purchase agreement unless it can be demonstrated that the true average lifetime is smaller than what is advertised. A random sample of 50 lightbulbs was selected, the lifetime of each bulb determined, and the appropriate hypotheses were tested using computer software, which gave the following results.
Variable N Mean St Dev SEMean Z P-Value
lifetime 50 738.44 38.20 5.40 -2.14 0.016
1. What conclusion would be appropriate for a significance level of.05?
2. What significance level would you recommend?
Answer:
a) For this case since the p value is lower than the significance level of 0.05 we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly lower than 750 hours
b) We can use a significance level minimum of 2% in order to ensure the conditions in favor to the alternative hypothesis and then the potential customer will decide to move forward with a purchase witht his condition.
Step-by-step explanation:
For this case we have the following info given after conduct the following system of hypothesis:
Null hypothesis: [tex]\mu \geq 750[/tex]
Alternative hypothesis: [tex]\mu< 750[/tex]
The output is:
Variable N Mean St Dev SEMean Z P-Value
lifetime 50 738.44 38.20 5.40 -2.14 0.016
For this case the statistic calculated was:
[tex] z = -2.14[/tex]
And the p value calculated is:
[tex] p_v =p(z<-2.14) = 0.016[/tex]
Part a
For this case since the p value is lower than the significance level of 0.05 we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly lower than 750 hours
Part b
We can use a significance level minimum of 2% in order to ensure the conditions in favor to the alternative hypothesis and then the potential customer will decide to move forward with a purchase witht his condition.
Susan designed a circular pool with diameter of 25 meters. What is the area of the bottom of the pool?
Answer: Area = 490.87 meters
Step-by-step explanation:
A=πr2
r = 12.5 (1/2 of diameter)
A = 490.87 meters
Step-by-step explanation:
We know that the formula to find the area of a circle is πr^2 or in other words, pi times the radius squared. We have been given the diamter of 25 inches. We know that the diamater is double the radius. 25 divided by 2 will get us 12.5. If we write this in equation form (or substitute the variables) will be written as: (3.14)12.5^2, 3.14 being pi. Now, we would multiply the radius by radius (because it's squared) or in other words, (12.5*12.5) to equal 156.25. If we write this in equation form, we would get: 3.14(156.25). Now we finally multiply pi (3.14) times 156.25 to equal 490.625 or rounded to the tenth 490.6
is –68 + 90 positive or negative?
Answer:
22. positive
Step-by-step explanation:
–68 + 90
22
