Question

2. A study is being conducted to compute the price of a hand cream. The researcher...

2. A study is being conducted to compute the price of a hand cream. The researcher needs the error range of the price to be within $1, and suspects that the population standard deviation would be around $29.
a. What sample size would we require if we desired a 99 percent confidence level?
b. What about if we keep the confidence level 95%, but decide that our acceptable error is $4?
Math   Statistics-And-Probability   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

a) The minimum sample with a given standard deviation

=29 at a 99% confidence interval is calculated as:

Where Zc is the critical value at a 99% confidence interval calculated using excel formula =NORM.S.INV(0.995) which results in Zc=2.576

and E is margin of error E=1

Now the minimum sample is calculated as:

b) If the confidence interval is 95% the Zc value changes which are again calculated using excel formula for normal distribution as =NORM.S.INV(0.975) which results in Zc=1.96

and given that E, the margin of error= 4.

The Minimum sample is calculated as:

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
1. A researcher expects the population proportion of FIFA fans in Abu Dhabi to be 80...
1. A researcher expects the population proportion of FIFA fans in Abu Dhabi to be 80 percent. The researcher wishes to have an error of less than 5 percent and to be 98 percent confident of an estimate to be made from a mail survey. What sample size is required? 2. A study is being conducted to compute the price of a hand cream. The researcher needs the error range of the price to be within $1, and suspects that...
1. To estimate the standard error of the mean, a survey researcher will: Select one: a....
1. To estimate the standard error of the mean, a survey researcher will: Select one: a. take the square root of the sample standard deviation. b. none of the above. c. multiply the sample standard deviation times the square root of the sample size. d. divide the sample standard deviation by the square root of sample size. 2. Suppose that a business researcher is attempting to estimate the amount that members of a target market segment spend annually on detergent...
A medical researcher would like to determine how effective a new form of knee surgery is...
A medical researcher would like to determine how effective a new form of knee surgery is for treating knee pains. (In particular, is there a relationship between surgery status and pain reduction status?) He gathers 500 people with knee pain who are scheduled to have this surgery, and 500 people with knee pain who are not scheduled to have this surgery. He follows up with both groups after 2 months and determines the number of participants of each group who...
1. A social researcher wants to test the hypothesis that people who drink a lot while...
1. A social researcher wants to test the hypothesis that people who drink a lot while bowling have higher scores than people who do not drink while they bowl. The researcher studies 50 drinking bowlers and 50 non-drinking bowlers. The average score for drinking bowlers was 142 with a standard deviation of 7.45. The average score for non-drinking bowlers was 134 with a standard deviation of 6.81. In words: What are your conclusions about the null hypothesis? 2. A social...
i. A researcher estimated the proportion of voters who favor the Democratic candidate in an election....
i. A researcher estimated the proportion of voters who favor the Democratic candidate in an election. Based on 500 people she calculates the 95% confidence interval for the population proportion p:   0.123 <p<0.181. Which of the following is a valid interpretation of this confidence interval ?______ a. There is a 95% chance that the true value of p lies between 0.123 and 0.181 b.   If many different samples of 500 were selected and a confidence interval was constructed based on...
Many people believe that the moon influences the actions of some individuals. A study of dementia...
Many people believe that the moon influences the actions of some individuals. A study of dementia patients in nursing homes recorded various types of disruptive behaviors every day for 12 weeks. Days were classified as moon days if they were in a three-day period centered at the day of the full moon. For each patient the average number of disruptive behaviors was computed for moon days and for all other days. The data for the 15 subjects whose behaviors were...
Student # Gender Height Shoe Age Hand 1 F 68 8.5 20 R 2 F 60...
Student # Gender Height Shoe Age Hand 1 F 68 8.5 20 R 2 F 60 5.5 27 R 3 F 64 7 31 R 4 F 67 7.5 19 R 5 F 65 8 20 R 6 F 66 9 29 R 7 F 62 9.5 30 L 8 F 63 8.5 18 R 9 F 60 5 19 L 10 F 63 7.5 42 R 11 F 61 7 20 R 12 F 64 7.5 17 R 13...
Roles What do they know Sales Manager You want to sell 10,000 units in April, 15,000...
Roles What do they know Sales Manager You want to sell 10,000 units in April, 15,000 in May, 8,000 units in June at $20 each. Business Development You know that our competitor is struggling with manufacturing and supply is low, and your POV is that demand will increase by 10% in April and May Manufacturing Supervisor You have seen that raw material supply shipments are being delayed - and you want to keep 15% of next months production needs on...
what is the issue in Emaar case study ? (10marks) Emaar Properties specializes in creating value-added,...
what is the issue in Emaar case study ? (10marks) Emaar Properties specializes in creating value-added, master-planned communities that meet the full spectrum of lifestyle needs. Highlights include Downtown Dubai, the 500-acre mega-project including Burj Khalifa – the world’s tallest building, and The Dubai Mall—the world’s largest shopping and entertainment destination. Emaar is extending its expertise in developing master-planned communities internationally, and has established operations in the United Arab Emirates, Saudi Arabia, Syria, Jordan, Lebanon, Egypt, Morocco, India, Pakistan, Turkey,...
Answer the question. CHAPTER 8: ESTIMATION AND CONFIDENCE INTERVALS 1. As degrees of freedom increase, the...
Answer the question. CHAPTER 8: ESTIMATION AND CONFIDENCE INTERVALS 1. As degrees of freedom increase, the t-distribution approaches the: A. binomial distribution B. exponential distribution C. standard normal distribution D. None of the above 2. Given a t-distribution with 14 degrees of freedom, the area left of - 1.761 is A. 0.025 B. 0.05 C. 0.10 D. 0.90 E. None of the above 3. 100 samples of size fifty were taken from a population with population mean 72. The sample...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT