Answers
Answer:
C: 4 hours
Step-by-step explanation:
Mean = Σxn/n
Σx/n = ((2 × 4) + (3 × 5) + (4 × 6) + (5 × 3) + (6 × 3) + (7 × 0) + (8 × 1))/(4 + 5 + 6 + 3 + 3 + 0 + 1)
Σx/n = 88/22
Σx/n = 4 hours
Related Questions
A fitness center is interested in finding a 90% confidence interval for the mean number of days per week that Americans who are members of a fitness club go to their fitness center. Records of 219 members were looked at and their mean number of visits per week was 2.4 and the standard deviation was 2.9. Round answers to 3 decimal places where possible.
A. The sampling distribution follows a _______ distribution.
B. With 90% confidence the population mean number of visits per week is between _____ and ______ visits.
C. If many groups of 220 randomly selected members are studied, then a different confidence interval would be produced from each group. About ________ percent of these confidence intervals will contain the true population mean number of visits per week and about__________ percent will not contain the true population mean number of visits per week.
Answers
Answer:
A. Normal
B. Between 2.078 and 2.722 visits.
C. About 90 percent of these confidence intervals will contain the true population mean number of visits per week and about 10 percent will not contain the true population mean number of visits per week.
Step-by-step explanation:
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]
x% confidence interval:
A confidence interval is built from a sample, has bounds a and b, and has a confidence level of x%. It means that we are x% confident that the population mean is between a and b.
Question A:
By the Central Limit Theorem, normal.
Question B:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.9}{2} = 0.05[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.05 = 0.95[/tex], so Z = 1.645.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
[tex]M = 1.645\frac{2.9}{\sqrt{219}} = 0.322[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 2.4 - 0.322 = 2.078 visits
The upper end of the interval is the sample mean added to M. So it is 2.4 + 0.322 = 2.722 visits.
Between 2.078 and 2.722 visits.
Question c:
90% confidence level, so 90% will contain the true population mean, 100 - 90 = 10% wont.
About 90 percent of these confidence intervals will contain the true population mean number of visits per week and about 10 percent will not contain the true population mean number of visits per week.
Emilio’s truck has a gas tank that holds 25 gallons of gas and can travel 400 miles without refilling the gas tank. The graph below shows the amount of gas remaining in Emilio’s truck after he has driven a certain number of miles. Which of the following best describes a reasonable range for this situation
Answers
Answer:
[tex]Range: 0 \le y \le 400[/tex]
Step-by-step explanation:
Given
[tex]Gas = 25 gallons[/tex]
[tex]Distance = 400miles[/tex] --- max
Required
The range of the function
The graph is not given; however, the question can be answered without the graph.
From the question, we understand that the truck can hold up to 25 gallons.
This represents the domain (i.e. from 0 to 25)
When the truck is empty (i.e. no gas in it), the truck cannot move any distance (0 miles).
When the truck is filled up (i.e. 25 gallon), the truck can move up to 400 miles.
This represents the range (i.e. from 0 to 400 miles)
Hence, the range is:
[tex]Range: 0 \le y \le 400[/tex]
please help i don't understand this question
A the cost of buying the tablet
B the cost per month of internet service
C the number of months after wich the total cost is 0 dollars
D none of the above
Answers
Answer:
Pretty sure it would be b because it keeps scaling as the x axis continues with time
Mr. Newman owns a sporting good store. He got a shipment of 49 baseball bats. 21 of them were wooden bats, and the rest were aluminum. What fraction of the bats were wooden?
Fill in the answer in simplest form.
Answers
Answer:
3/7
Step-by-step explanation:
10. Which of these is NOT a perfect square?
a. 81
b. 100
C. X2
d. 42
Answers
Answer: 42 is not a square of a whole number
Step-by-step explanation: 81= 9², 100= 10², x²= x·x, 6²= 36 and 7²= 49
The original price of a book is $25. The book is on sale for 30% off.
What percent of the price are we paying? What is the price you will pay
for the book?
Answers
Answer:
You will pay 70% of the original price. You will pay $17.50
Step-by-step explanation:
100% is full price because 100%=1 (one whole).
100% - 30% = 70%
70% = 0.7
0.7 multiplied by $25 is $17.50
Help please.......I’ll give u brain liest
Answers
Answer:
Step-by-step explanation:
Hope this helps
Round to one billion place. Drop the zeros.
28,436,297,825
30,943,267,101
45,831,246,935
Answers
Answer:
28,436,297,825
30,943,267,101
45,000,000,000
Step-by-step explanation:
ur welcome
If Jordan rode his bike for five days how much hours dose he ride it for? PLEASE COMMENT YOUR ANSWER asp
Answers
Answer: 2880 hours
Explanation: 120 days times 24 hours
Melinda said that the fort would melt in the fourth month of the year. What month will the fort melt?
Answers: February, March, and April
Answers
Answer:
april
Step-by-step explanation:
Answer:
April is the fourth month of the year! Hope this helps.
Step-by-step explanation:
Based on the Nielsen ratings, the local CBS affiliate claims its 11:00 PM newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is the Alternate hypothesis
Answers
Answer:
Alternative Hypothesis:H₁: μ ≠ 0.41
Step-by-step explanation:
Step(i):-
Given that the newscast reaches 41% of the viewing audience in the area
The mean of the Population = 0.41
Given that In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station
Given that the mean of the sample = 0.36
Step(ii):-
Null hypothesis: The sample statistic does not differ significantly from the hypothetical parameter value.
Given data
Null hypothesis: H₀ : μ = 0.41
Alternative Hypothesis: Any hypothesis which is complementary to the Null hypothesis
Alternative Hypothesis:H₁: μ ≠ 0.41
Please help me! This is due tomorrow and I really need some help! Thank you.
Answers
Answer:
over 1/2 own a dog
Step-by-step explanation:
Answer:
Over 1/2 of students own a dog.
Step-by-step explanation:
Total number of students: 25 Add the students owning different types of pets
13/25 Number of students owning dogs divided by total number of students
13/26 = 1/2; therefore 13/25 > 1/2
1) Determine the area of the shaded region.
14 ft
8 ft
Answers
Answer:
61.73 ft ^2
Step-by-step explanation:
area of rectangle
14x8 = 112
area of circle
π(4)(4) = 50.27
subtract
112-50.27 = 61.73
Yuhhh please help ty :))
Answers
Answer:
20 oz.
Step-by-step explanation:
Hope this helps ! :)
An angle measures 60.2° less than the measure of its supplementary angle. What is the measure of each angle?
Answers
Answer:
the angles are 120.1 and 59.9
Step-by-step explanation:
supplementary means that the add up to be 180
I made a system of equations and to make thing faster I graphed them but if you wanted you could solve fully
x+y=180
y-60.2=x
Write the explicit rule
a1=5 d=4
Answers
Let a_1 = 5
Let d = 5 = common difference
S_n = a_1 + (n - 1)d
S_n = 5 + (n - 1)4
Find the average of the function over the given interval. f(x) = x3 over [−1, 1]
Answers
9514 1404 393
Answer:
0
Step-by-step explanation:
f(x) = x^3 is an odd function, so is symmetrical about the origin. Its average value on any symmetrical interval around the origin will be 0.
The average value is 0.
hellllllp !!!!!!!!!!!!!!!!!!!!!!!!
Answers
Answer:
N is the midpoint.
Step-by-step explanation:
what is the value of 5 in (and the three on the top
Answers
Answer:
5^3 = 125
Step-by-step explanation:
5^3
5 x 5 x 5
=125
Answer:
[tex]5^{3} = 125[/tex]
Step-by-step explanation:
Mark me brainllest
Find the area of this parallelogram, top= 14 left= 11 right = 10
Answers
Answer:
140 cm^2
Step-by-step explanation:
Formula for area of a Parallelogram: base*height
14 cm * 10cm = [tex]140 cm^{2}[/tex]
In a study of academic procrastination, the authors of a paper reported that for a sample of 451 undergraduate students at a midsize public university preparing for a final exam in an introductory psychology course, the mean time spent studying for the exam was 7.74 hours and the standard deviation of study times was 3.10 hours. For purposes of this exercise, assume that it is reasonable to regard this sample as representative of students taking introductory psychology at this university.
(a) Construct a 95% confidence interval to estimate μ, the mean time spent studying for the final exam for students taking introductory psychology at this university. (Round your answers to three decimal places.) TWO VALUES
(b) The paper also gave the following sample statistics for the percentage of study time that occurred in the 24 hours prior to the exam.
n = 451 x = 43.78 s = 21.96
Construct a 90% confidence interval for the mean percentage of study time that occurs in the 24 hours prior to the exam. (Round your answers to three decimal places.)
Answers
Answer:
a) The 95% confidence interval to estimate μ is (7.435, 8.045) hours.
b) The 90% confidence interval for the mean percentage of study time that occurs in the 24 hours prior to the exam is (41.079%, 45.481%).
Step-by-step explanation:
Question a:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
[tex]M = 1.96\frac{3.3}{\sqrt{451}} = 0.305[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 7.74 - 0.305 = 7.435 hours
The upper end of the interval is the sample mean added to M. So it is 7.74 + 0.305 = 8.045 hours.
The 95% confidence interval to estimate μ is (7.435, 8.045) hours.
Question b:
90% confidence interval means that [tex]Z = 1.645[/tex]
The margin of error is:
[tex]M = 1.645\frac{21.96}{\sqrt{451}} = 1.701[/tex]
43.78 - 1.701 = 41.079%
43.78 + 1.701 = 45.481%
The 90% confidence interval for the mean percentage of study time that occurs in the 24 hours prior to the exam is (41.079%, 45.481%).
solve 6×1/5 solve the equation
Answers
Step-by-step explanation:
6/5is the answer................
Answer:
1 and 1/5
Step-by-step explanation:
6 times 1/5 is 1/5+1/5+1/5+1/5+1/5+1/5 which equals to 6/5 which also equals to 1 and 1/5
A police officer claims that the proportion of drivers wearing a seat belt in a certain area is less than 40%. To test this claim, the officer collects a random sample of 80 drivers and monitors if the driver was wearing a seat belt. From this sample of 80 drivers, the police offers observes that 34 were wearing seat belts. Assume the conditions needed to conduct a one sample proportion test are satisfied. The setup for the null and alternative hypothesis is as follows: H0:p=0.40; Ha:p<0.40, which is a left-tailed test. The test statistic and p-value for this Hypothesis test are given as follows: z=0.456, p-value=0.676. Which of the following are appropriate conclusions for this hypothesis test? Select all that apply.
Answers
Answer:
Fail to reject the null because the p-value is greater than significance level (0.05). Therefore we have convincing evidence that the proportion of drivers wearing a seat belt is equal to 40%.
Step-by-step explanation:
I am assuming that the significance level is 0.05, so we would fail to reject the null, because the p-value is 0.676 which is greater than the significance level. Whenever the p-value is greater than the signifigance level we fail to reject the null.
What is the result of subtracting the second equation from the first?
8x - 4y = -4
-3x + 4y = 5
Answers
Answer:
See belowStep-by-step explanation:
Given system:
8x - 4y = -4 -3x + 4y = 5Subtracting the second equation from the first:
8x - 4y - (-3x + 4y) = -4 - 58x + 3x - 4y - 4y = -911x - 8y = -9It ends here
============================
Would be better to add the equations to eliminate y and solve the system:
8x - 4y + (-3x + 4y) = -4 + 55x = 1x = 0.2Find y:
8*0.2 - 4y = -44y = 1.6 + 44y = 5.6y = 1.4Solution (0.2, 1.4)
How many times greater is the value of the 9 digit in 90,523 than the 9 digit in 59,112?
Answers
Answer:
I'm pretty sure it's 10,000
Plz I need help with this
Answers
Answer:56
Step-by-step explanation:
Find the domain of the function in interval notation: f(x) =1/ x + 22
Answers
That's the answer
x = - 1/22
Find the amount due if $200 is borrowed for 10 months at an APR of 16% simple interest
Amount =?
Answers
Answer
$266.66
Step-by-step explanation:
We have here ,
Principal = $200 Rate = 16% Time = 10 months = 10/12 yrs.We can use the formula of SI to calculate the SI . After adding it to principal we will get the amount .
⇒ SI = P × R × T / 100
⇒ SI = $ 200 × 16 × 10 / 12 × 100
⇒ SI = $ 26.66
Now Calculate amount as ,
⇒ A = SI + P
⇒ A = $ 200 + $ 26.66
⇒ A = $ 226.66
How come the tutors don't work??
Answers
Answer:
What do you mean? If you are talking about the Community not always answering Questions well that means your they don't know the right Answer
the Mods are Annoying and very skeptic of the Guidelines of Brainly.
40 pts please help!
Which of the following is a tangent line to circle O?
a. line EF
b. segment OD
c. segment BC
d. line AG
Answers
Answer:
d.
Step-by-step explanation:
line AG is the answer because a tangent line to a circle is a line that touches the circle at exactly one point, never entering the circle's interior.
Answer:
d. line AG
Step-by-step explanation:
A tangent is a line that just 'touches' the curve of a circle, and doesn't intersect it.
We can see that since AG touches the circle, and since the other lines all intersect the circle, the tangent here is AG