Question
In: Statistics and Probability
The owner of a petrol station wants to study fuel-purchasing habits of motorists at his station....
The owner of a petrol station wants to study fuel-purchasing habits of motorists at his station. A random sample of 60 motorists during a particular week gave the following results:
Amount purchased: X= 42.8 litres, S =10.3 litres.
9 motorists purchased diesel.
(a) Set up a 95% confidence interval estimate for the proportion of motorists who buy diesel. Write a sentence to explain the meaning of your answer.
Confidence interval:
Explanation:
(b) Set up a 95% confidence interval estimate for the mean amount of fuel purchased by a customer. Write a sentence to explain the meaning of your answer.
Confidence interval:
Explanation:
(c) Before carrying out the survey, the owner thought that 10% of his customers used diesel, and that the average amount of fuel was no more than 40 litres per customer. Do the results of the survey suggest that he was wrong? Explain.
(d) Do we need to assume for the analysis in (b) that the amounts purchased follow a normal distribution? Discuss.
Solutions
orchestra answered 2 years agoRelated Solutions
The owner of a gas station wants to study gasoline purchasing habits of motorists at this...
The owner of a gas station wants to study gasoline purchasing
habits of motorists at this station. He selects a random sample of
60 motorists during a certain week, with the following results: The
amount of gas purchased was; mean = 11.3 gallons, standard
deviation = 3.1 gallons; Eleven motorists purchased premium-grade
gasoline (4 points)
At the 0.05 significance level, is there evidence that the
population mean purchase was different from 10 gallons? (1
point)
Determine the p-value in part...
The owner of a gas station wants to study gasoline purchasing habits of motorists at this...
The owner of a gas station wants to study gasoline purchasing
habits of motorists at this station. He selects a random sample of
60 motorists during a certain week, with the following results: The
amount of gas purchased was; mean = 11.3 gallons, standard
deviation = 3.1 gallons; Eleven motorists purchased premium-grade
gasoline (4 points)
At the 0.05 significance level, is there evidence that the
population mean purchase was different from 10 gallons? (1
point)
Determine the p-value in part...
3. The owner of a gasoline station wants to study gasoline purchasing habits by motorists at...
3. The owner of a gasoline station wants to study gasoline
purchasing habits by motorists at his station. He selects a random
sample of 55 motorists during a certain week, with the following
results:
The amount purchased was XBar = 11.0 gallons, S = 3.3
gallons.
15 motorists purchased premium-grade gasoline.
At the 0.05 level of significance, is there evidence that the
population mean purchase was different from 10 gallons?
At the 0.1O level of significance, is there evidence that...
The owner of a specialty coffee shop wants to study coffee purchasing habits of customers at...
The owner of a specialty coffee shop wants to study coffee
purchasing habits of customers at her shop. She selects
a random sample of 60 customers during a certain week. Data are
available in the worksheet labeled “Problem 2”
in the spreadsheet.
1. Construct a 90% confidence interval on the proportion of
customers who say they “definitely will”
recommend the specialty coffee shop to family and friends.
Problem 2 Data Set
Note: Y is an indicator variable, i.e., if Y=1,...
The owner of a specialty coffee shop wants to study coffee purchasing habits of customers at...
The owner of a specialty coffee shop wants to study coffee
purchasing habits of customers at her shop. She selects a random
sample of 60 customers during a certain week. Data are available in
the worksheet labeled “Problem 2” in the spreadsheet
Final_SU2020_Data_Sets.xlsx. 1. At the ? = 0.1 level of
significance, is there evidence that more than 50% of the customers
say they “definitely will” recommend the specialty coffee shop to
family and friends? 2. Construct a 90% confidence...
The owner of a specialty coffee shop wants to study coffee purchasing habits of customers at...
The owner of a specialty coffee shop wants to study coffee
purchasing habits of customers at her shop. She selects a random
sample of 60 customers during a certain week. Data are available in
the worksheet labeled “Problem 2”.
1. At the a = 0.1 level of significance, is there evidence that
more than 50% of the customers say they “definitely will” recommend
the specialty coffee shop to family and friends?
2. Construct a 90% confidence interval on the proportion...
The owner of a specialty coffee shop wants to study coffee purchasing habits of customers at...
The owner of a specialty coffee shop wants to study coffee
purchasing habits of customers at her shop. She selects a random
sample of 60 customers during a certain week, with the following
results:
• The amount spent was X = +7.25, S = +1.75.
• Thirty-one customers say they “definitely will” recommend
the specialty coffee shop to family and friends.
a. At the 0.05 level of significance, is there evidence that
the population
mean amount spent was different from...
4. The owner of specialty coffee shop wants to study coffee purchasing habits of customers at...
4. The owner of specialty coffee shop wants to study coffee
purchasing habits of customers at her shop. She selects a random
sample of 60 customers during certain week, with the following
results:
The amount spent was ? = $7.25, S = $1.75
Thirty-one customers say they definitely will” recommend the
specialty coffee shop to family friends.
a. At the 0.05 level of significance, is there evidence that the
population mean amount spent was different from $6.50? (IS THIS
RIGHT?)...
4. The owner of specialty coffee shop wants to study coffee purchasing habits of customers at...
4. The owner of specialty coffee shop wants to study coffee
purchasing habits of customers at her shop. She selects a random
sample of 60 customers during certain week, with the following
results:
The amount spent was ? = $7.25, S = $1.75
Thirty-one customers say they definitely will” recommend the
specialty coffee shop to family friends.
a. At the 0.05 level of significance, is there evidence that the
population mean amount spent was different from $6.50?
b. Determine the...
The owner of a restaurant that serves continental food wants to study characteristics of his customers....
The owner of a restaurant that serves continental food wants to
study characteristics of his customers. He decides to focus on two
variables: the amount of money spent by customers and whether
customers order dessert. The results from a sample of 60 customers
are as follows:
• Amount spent ( =$38.54, S=
$7.26)
• 18 customers purchased dessert.
Construct a 95% confidence interval estimate of the population
mean amount spent per customer in the restaurant.
_____________
Construct a 90% confidence...
ADVERTISEMENT
ADVERTISEMENT
Latest Questions
- (2) Cite an example on how organizations like Google, Facebook, Youtube etc collect data for image...
- The legal landscape is perpetually changing. Psychologists must remain abreast of these changes to avoid potentially...
- We are evaluating a project that costs $1.68 million, has a six-year life, and has no...
- In C++ Having call-by-reference allows one to use storeback parameters, i.e., parameters whose values are transmitted...
- You must evaluate a proposal to buy a new milling machine. The base price is $175,000,...
- “Triangle Guessing” game in Python The program accepts the lengths of three (3) sides of a...
- THIS PROGRAM HAS TO BE WRITTEN IN C Single function to perform the parity computation on...
ADVERTISEMENT