Calculus and Above

Calculus Questions? Ask a Mathematician for Answers ASAP

Ask an Expert,
Get an Answer ASAP!

Calculus and Above

1) Question 1 (Q3)- a random sample of n=100 observations is

Customer Question
selected from a population with...
1) Question 1 (Q3)- a random sample of n=100 observations is selected from a population with µ=30 and o=23. Approximate the probabilities shown below.
a. P(x̄ ≥28
b. P(22.1≤ x̄ ≤ 26.8)
c. P(x̄≤ 28.2)
d. P(x̄≥ 27.0)
Submitted: 5 years ago.Category: Calculus and Above
Show More
Show Less
Ask Your Own Calculus and Above Question
Answered in 14 minutes by:
7/2/2012
Tutor: Ray Atkinson, Bachelor's Degree replied 5 years ago
Ray Atkinson
Ray Atkinson, Bachelor's Degree
Category: Calculus and Above
Satisfied Customers: 1,890
Experience: Inner-city high school substitute teacher. Degrees in mathemetics, accounting, and education. Years and years of tutoring.
Verified

Correct me if I am wrong.

That is a mean of 30 and a standard deviation of 23?

Ask Your Own Calculus and Above Question
Customer reply replied 5 years ago



1) Question 1 (Q3)- a random sample of n=100 observations is selected from a population with µ=30 and o=23. Approximate the probabilities shown below.
a. P(x̄ ≥28
b. P(22.1≤ x̄ ≤ 26.8)
c. P(x̄≤ 28.2)
d. P(x̄≥ 27.0)

2) Question 2 ( Q4)- The average salary from certain profession is $82,000. Assume that the standard deviation of such salaries is $32,000. Consider a random sample of 58 people in the profession and let x represent the mean salary for the sample.
E. find P (x̄ > 72,500 =

3) Question 3 (Q5)- A random sample of 91 Observation produced a mean x̄ = 25.4 and a standard deviations s=2.4.
a. Find a 95% confidence interval for µ (use intervals or decimals for any numbers in the expression. Round to two decimals places as needed.)
b. Find a 90% confidence interval for µ (use intervals or decimals for any numbers in the expression. Round to two decimals places as needed.)
c. Find a 99% confidence interval for µ (use intervals or decimals for any numbers in the expression. Round to two decimals places as needed.)


4) Question 4 (Q6)- The mean and the standard deviation of a random sample of n measurements are equal to 33.4 and 3.9, respectively.
a. Find a 95% confidence interval for µ if n= 144
b. Find a 95% confidence interval for µ if n= 576
c. Find the widths of the confidence intervals found in parts a and b. What is the effect on the width of a confidence interval of quadrupling the sample size while holding the confidence coefficient fixed?

5) Question 5 (Q8)- A newspaper reported that 8% of people say that some coffee shops are overprices. The source of this information was a telephone survey of 500 adults.
d. Find and interpret a 90% confidence interval for the parameter of the interest
( , ).

6) Question6 (Q9)- Researchers conducted a study of variety in exercise workouts. A sample of 120 men and women were randomly divided into three groups, with 40 people per group. Group 1 members varied their exercise routine in workouts, group 2 members performed the same exercise are each workout, and group 3 members had no set schedule or regulation for their work outs.
a. By the end of the study, 18 people had dropped out of the first exercise group. Estimate the dropout rate for exercisers who vary their routine in workouts?
b. By the end of the study, 25 people had dropped out of the third exercise group. Estimate the dropout rate for exercisers who have no set schedule for their workouts. Use a 90% confidence interval and interpret the result.

7) Question 7 ( Q10) –If you wish to estimate a population mean with a sampling distribution error SE=0.32nusing a 95% confidence interval and you know from prior sampling that o2 is approximately equal to 8.3, how many observations would have to be included in your sample?
a. The number of observations that would have to be included in your sample is (round up the nearest observation)

8) Question 8 (Q11)- Suppose N=5,000,n=1,000, and s=50
a. Compute the standard error of x̄ using the finite population correction factor
b. Repeat part assuming n=2,000.
c. Repeat part a assuming n=5,000
d. Compare parts a, b, c , and describe what happens to the standard error of x as n is increased.

9) Question 9 (Q12) – Suppose you want to estimate a population proportion, p, and ̂p=0.31, N=6100, and n=1700. Find an approximate 95% confidence interval for p.
a. An approximate 95% confidence interval for p is + .

10) Question 10 (Q13)- A random sample of size n= 20 was drawn from a population of size N= 220. The measurements shown in the table below were obtained.

40 28 43 22
33 27 47 21
55 40 27 35
18 39 39 36
48 49 53 53

a. Estimate µ with an approximate 95% confidence interval. (round the three decimal places as needed).
b. Estimate p, the proportion of measurements in the population that are greater than 30, with an approximate 95% confidence interval.

11) Question 11( Q14)- The random sample shown below was selected from a normal distribution. 8,8,4,7,7,2
a. Construct a 99% confidence interval for the population mean µ. ( , ) ( round to two decimal places as needed).
b. Assume that sample mean x̄ and sample standard deviation s remain exactly the same as those you just calculated but that are based on a sample of n=25 observations. Repeat part a. what is the effect of increasing the sample size on the width of the confidence intervals.




12) Question 12 (Q15)- in order to evaluate the reasonableness of firm’s stated total value of its parts inventory, as auditor randomly samples 50 of the total 300 parts in stock, process each part, and reports the results shown in the table. Use this information to answer the following question
Part price $52 $90 $12 $57 $98 $85 $70 $99
Sample Size 7 3 10 3 7 6 7 7

a. Give a point estimate of the mean of the value of the parts inventory. $ (round to the nearest cent as needed).
b. Find the estimate standard error of the point estimate of part a.
c. Find the limit


 


Optional Information:
Level/Year: 16




Tutor: Ray Atkinson, Bachelor's Degree replied 5 years ago
I am not sure enough of my answers. I will opt out for someone better confident.
Ask Your Own Calculus and Above Question
Tutor: Trigeoscal, Master's Degree replied 5 years ago
Trigeoscal
Trigeoscal, Master's Degree
Category: Calculus and Above
Satisfied Customers: 530
Experience: Math Homework, Pre Calculus and Calculus and Above
Verified
1) Question 1 (Q3)- a random sample of n=100 observations is selected from a population with µ=30 and o=23. Approximate the probabilities shown below.
a. P(x̄ ≥28 )

answer: 0.8077

b. P(22.1≤ x̄ ≤ 26.8)

answer: 0.0818

c. P(x̄≤ 28.2)

answer: 0.2169

d. P(x̄≥ 27.0)

answer: 0.9039


2) Question 2 ( Q4)- The average salary from certain profession is $82,000. Assume that the standard deviation of such salaries is $32,000. Consider a random sample of 58 people in the profession and let x represent the mean salary for the sample.
E. find P (x̄ > 72,500) =

Answer 0.9881


3) Question 3 (Q5)- A random sample of 91 Observation produced a mean x̄ = 25.4 and a standard deviations s=2.4.
a. Find a 95% confidence interval for µ (use intervals or decimals for any numbers in the expression. Round to two decimals places as needed.)

Answer: 24.91 < µ < 25.89


b. Find a 90% confidence interval for µ (use intervals or decimals for any numbers in the expression. Round to two decimals places as needed.)

Answer: 24.99 < µ < 25.81


c. Find a 99% confidence interval for µ (use intervals or decimals for any numbers in the expression. Round to two decimals places as needed.)

Answer: 24.75 < µ < 26.05


4) Question 4 (Q6)- The mean and the standard deviation of a random sample of n measurements are equal to 33.4 and 3.9, respectively.
a. Find a 95% confidence interval for µ if n= 144

Answer: 32.76 < µ < 34.04


b. Find a 95% confidence interval for µ if n= 576

Answer: 33.08 < µ < 33.72

c. Find the widths of the confidence intervals found in parts a and b.

Answer:

width for a is 0.6370

width for b is 0.3185

What is the effect on the width of a confidence interval of quadrupling the sample size while holding the confidence coefficient fixed?

Answer:

the width is reduced by half

5) Question 5 (Q8)- A newspaper reported that 8% of people say that some coffee shops are overprices. The source of this information was a telephone survey of 500 adults.
d. Find and interpret a 90% confidence interval for the parameter of the interest
( , ).

Answer:

(0.06, 0.10)

This means that there is 90% chance that the true proportions of people saying that some coffee shops are overprices is within the interval (0.06, 0.10) or to be exact up to 6 decimals: within the interval (0.060044, 0.099956)


6) Question6 (Q9)- Researchers conducted a study of variety in exercise workouts. A sample of 120 men and women were randomly divided into three groups, with 40 people per group. Group 1 members varied their exercise routine in workouts, group 2 members performed the same exercise are each workout, and group 3 members had no set schedule or regulation for their work outs.
a. By the end of the study, 18 people had dropped out of the first exercise group. Estimate the dropout rate for exercisers who vary their routine in workouts?

answer: point estimate or sample proportion = 18/40 or 0.45


b. By the end of the study, 25 people had dropped out of the third exercise group. Estimate the dropout rate for exercisers who have no set schedule for their workouts. Use a 90% confidence interval and interpret the result.


answer:

(0.4991, 0.7509)


7) Question 7 ( Q10) –If you wish to estimate a population mean with a sampling distribution error SE=0.32nusing a 95% confidence interval and you know from prior sampling that o2 is approximately equal to 8.3, how many observations would have to be included in your sample?
a. The number of observations that would have to be included in your sample is (round up the nearest observation)


Answer: 311 (note: clarification is o2 variance?)




8) Question 8 (Q11)- Suppose N=5,000,n=1,000, and s=50
a. Compute the standard error of x̄ using the finite population correction factor

answer: 1.414355


b. Repeat part assuming n=2,000

answer: 0.866112



c. Repeat part a assuming n=5,000

answer: zero

d. Compare parts a, b, c , and describe what happens to the standard error of x as n is increased.


answer: a is greater than b and is greater than c

as n increases, the value of the standard error decreases



9) Question 9 (Q12) – Suppose you want to estimate a population proportion, p, and ̂p=0.31, N=6100, and n=1700. Find an approximate 95% confidence interval for p.
a. An approximate 95% confidence interval for p is + .

answer: (0.2913, 0.3287)

10) Question 10 (Q13)- A random sample of size n= 20 was drawn from a population of size N= 220. The measurements shown in the table below were obtained.

40 28 43 22
33 27 47 21
55 40 27 35
18 39 39 36
48 49 53 53

a. Estimate µ with an approximate 95% confidence interval. (round the three decimal places as needed).

answer: (32.625, 42.675)

b. Estimate p, the proportion of measurements in the population that are greater than 30, with an approximate 95% confidence interval.


answer: (0.508, 0.892)

11) Question 11( Q14)- The random sample shown below was selected from a normal distribution. 8,8,4,7,7,2
a. Construct a 99% confidence interval for the population mean µ. ( , ) ( round to two decimal places as needed).

answer: (1.97, 10.03)

b. Assume that sample mean x̄ and sample standard deviation s remain exactly the same as those you just calculated but that are based on a sample of n=25 observations. Repeat part a. what is the effect of increasing the sample size on the width of the confidence intervals.


answer: (4.63, 7.37)

Increasing the sample size decreases the width of the interval

12) Question 12 (Q15)- in order to evaluate the reasonableness of firm’s stated total value of its parts inventory, as auditor randomly samples 50 of the total 300 parts in stock, process each part, and reports the results shown in the table. Use this information to answer the following question
Part price $52 $90 $12 $57 $98 $85 $70 $99
Sample Size 7 3 10 3 7 6 7 7

a. Give a point estimate of the mean of the value of the parts inventory. $ (round to the nearest cent as needed).

answer: $66.08


b. Find the estimate standard error of the point estimate of part a.

answer:
$4.113089756 or approx $4.11


c. Find the limit

ANSWER:
($58.02, $74.14)

Please Leave a POSITIVE FEEDBACK to Credit me. BONUS is welcome.Thanks.

If you need my help asap, just write in the first part of your question: "For Mr Glenn G. only!" Thanks again


Thanks again. Don't forget to accept my answers if you are satisfied only, so that I will be compensated in helping you, thanks again!


Ask Your Own Calculus and Above Question
Tutor: Trigeoscal, Master's Degree replied 5 years ago
If you still have any more questions don't hesitate to ask me



Please Leave a POSITIVE FEEDBACK to Credit me. BONUS is welcome.Thanks.

If you need my help asap, just write in the first part of your question: "For Mr Glenn G. only!" Thanks again


Thanks again. Don't forget to accept my answers if you are satisfied only, so that I will be compensated in helping you, thanks again!
Ask Your Own Calculus and Above Question
Ask Trigeoscal Your Own Question
Trigeoscal
Trigeoscal
Trigeoscal, Master's Degree
Category: Calculus and Above
Satisfied Customers: 530
530 Satisfied Customers
Experience: Math Homework, Pre Calculus and Calculus and Above

Trigeoscal is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

SusanAthena

SusanAthena

Master's Degree

102 satisfied customers

Tutor for Algebra, Geometry, Statistics. Explaining math in plain English.

Mr. Gregory White

Mr. Gregory White

Master's Degree

99 satisfied customers

M.A., M.S. Education / Educational Administration

Dr Arthur Rubin

Dr Arthur Rubin

Doctoral Degree

58 satisfied customers

Ph.D. in Mathematics, 1978, from the California Institute of Technology, over 20 published papers

JACUSTOMER-yrynbdjl-

JACUSTOMER-yrynbdjl-

Master's Degree

42 satisfied customers

I have a MS in Mathematics and I have taught Mathematics for 10 years at the college level.

dhouse1940

dhouse1940

Master's Degree

33 satisfied customers

BS mathematics, MS biostatistics, 35+ yrs designing & analyzing biological experiments.

Don

Don

Master's Degree

29 satisfied customers

M.S. Astronautical Engineering. Math/Sci/Comp Tutor

mhasan420

mhasan420

Master's Degree

15 satisfied customers

BA Maths, Oxford

< Previous | Next >

Related Calculus and Above Questions
I want to know the answer of the question math. Families
Families USA, a monthly magazine that discusses issues related to health and health costs, surveyed 21 of its subscribers. It found that the annual health insurance premiums for a family with coverage through an employer averaged $10,650. The standard deviation of the sample was $1,025. Families USA, a monthly magazine that discusses issues related to health and health costs, surveyed 21 of its subscribers. It found that the annual health insurance premiums for a family with coverage through an employer averaged $10,650. The standard deviation of the sample was $1,025. Families USA, a monthly magazine that discusses issues related to health and health costs, surveyed 21 of its subscribers. It found that the annual health insurance premiums for a family with coverage through an employer averaged $10,650. The standard deviation of the sample was $1,025. … read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
For this assignment, collect data exhibiting a relatively
For this assignment, collect data exhibiting a relatively linear trend, find the line of best fit, plot the data and the line, interpret the slope, and use the linear equation to make a prediction. Al… read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
In his book Outliers, author Malcolm Gladwell argues that
In his book Outliers, author Malcolm Gladwell argues that more baseball players have birthdates in the months immediately following July 31, because that was the cutoff date for nonschool baseball lea… read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
How many women must be randomly selected to estimate the
How many women must be randomly selected to estimate the mean weight of women in one age group. We want​ 90% confidence that the sample mean is within 2.52.5 lb of the population​ mean, and the popula… read more
Ryan
Ryan
Bachelor\u0027s Degree
1,060 satisfied customers
This is a calculs 1 question I have the spherical cow is
This is a calculs 1 question I haveFred the spherical cow is happily grazing on cubical grass pellets. He grows in volume at a rate of 8 cubic feet per day.When Fred's radius is 11 feet at what rate i… read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
How can I get the answers to all of my questions. There are
There are several questions I would need answers to … read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
I'd very much like to work with you on a new project I have.
Hi Ryan,I'd very much like to work with you on a new project I have. I have attached the information and I'm looking forward to hearing form you soon.… read more
Ryan
Ryan
Bachelor\u0027s Degree
1,060 satisfied customers
According to a New York Times / CBS News poll in June 2012,
According to a New York Times / CBS News poll in June 2012, only about 44% of the American public approves of the job the Supreme Court is doing. This poll included responses of 976 adults.Estimate th… read more
Ryan
Ryan
Bachelor\u0027s Degree
1,060 satisfied customers
A doctor wants to estimate the HDL cholesterol of all 20-29
A doctor wants to estimate the HDL cholesterol of all 20-29 year old females. How many subjects are needed to estimate the HDL cholesterol within 2 points with ((% confidence assuming sigma is 18.2? S… read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
I need to find d as a function of t. My equation is: d^2 +
I need to find d as a function of t. My equation is: d^2 + 2Rd = c^2*t^2 Seems like I learned how to do this 40 years ago but have since forgotten.… read more
Ashok Kumar
Ashok Kumar
Master\u0027s Degree
291 satisfied customers
In a study of memory recall, 5 people were given 10 minutes
In a study of memory recall, 5 people were given 10 minutes to memorize a list of 20 words. Each was asked to list as many of the words as he or she could remember both 1 hour and 24 hours later. The … read more
Ryan
Ryan
Bachelor\u0027s Degree
1,060 satisfied customers
3. Find the top 20 states with the most number of total
3. Find the top 20 states with the most number of total murders. Then, calculate the mean, median, and mode. … read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
Need help figuring our Hypothsis test (p-value or critical
need help figuring our Hypothsis test (p-value or critical value) to determine proportion (math cassignment ) - Roocky University Dean of student report assignemt… read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
I am being asked to find the test statistic. Here is the
The claim is that the white blood cell count of adult females are normally distributed, with a standard deviation of 3.12. A random sample of 42 adult females has wbc with a mean of 7.44 and a standard deviation of 3.49.… read more
Ryan
Ryan
Bachelor\u0027s Degree
1,060 satisfied customers
Give an example of a discrete random variable. ​ a The time
RyanGive an example of a discrete random variable. ​ a The time required for a runner to finish a marathon b The number of beverages sold at a lemonade stand c. The number of gallons of concrete used … read more
Ryan
Ryan
Bachelor\u0027s Degree
1,060 satisfied customers
Can you tell me if a histogram has skewness? I have created
I have created 2 histograms and need to tell if they are symmetric, skewed, kurtosis, • Skew. • Kurtosis. • Outlier. • Symmetry. • Modality. … read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
Here it is. The questions are Explain the eight
The questions are Explain the eight characteristics of a normal distribution. Explain why converting raw scores to z scores is helpful in understanding data … read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
I need help with question number 2c using excel, I need help
I need help with question number 2c using excel JA: The Advanced Math Tutor can help you get an A on your homework or ace your next test. Tell me more about what you need help with so we can help you … read more
GLENN
GLENN
Master of Mathematics
330 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x