Question

In: Statistics and Probability

a trade magazine routinely checks the drive through service times of fast food restaurants. a 95%...

a trade magazine routinely checks the drive through service times of fast food restaurants. a 95% confidence interval that results from examining 605 customers in one fast food chains drive through has a lower bound of 170.1 seconds and upper bound of 173.1 seconds. what does this mean?

Solutions

Expert Solution

Confidence interval is a range of values that contain an unknown population parameter. Confidence interval contains the true value of the parameter when a random sample is drawn many times.

For the large samples the population parameter with more precision can be obtained. Therefore, confidence interval is based on sample observations.

Let denote the mean service time then it represents the population parameter

Let us understand the concept on the basis of confidence interval of mean for known standard deviation.

Then the confidence interval for level of significance is given by

The level of significance is generally expressed in percentage form then 100(1- )% represents the confidence interval.

=5% we have 95% confidence interval.

In many cases population parameter is unknown so to have an idea about the population parameter confidence interval is generally used in which there is high chances of population parameter to fall in that region.

Let us understand the concept using the sample. Let us assume that 100 samples of fast food restaurant is taken then 95% confidence interval indicates that out of 100 samples , the mean service times of fast food restaurant lies in an interval (170.1, 173.1) in 95 of those 100 samples. Also, if the same population is sampled in many number of time and in many occasions and if the confidence interval is obtained in each case, then in 95% of the samples the population parameter falls in the confidence interval in 95% of the samples. i.e. for 605 customer the mean service time of restaurant lies in (170.1, 173.1).


Related Solutions

Sparagowski & Associates conducted a study of service times at the drive-up window of fast-food restaurants....
Sparagowski & Associates conducted a study of service times at the drive-up window of fast-food restaurants. The average time between placing an order and receiving the order at McDonald's restaurants was 2.78 minutes (The Cincinnati Enquirer, July 9, 2000). Waiting times, such as these, frequently follow an exponential distribution. 1. What is the probability that a customer's service time is less than 2 minutes? 2. What is the probability that a customer's service time is more than 5 minutes? 3....
The accompanying data are​ drive-through service times​ (seconds) recorded at a fast-food restaurant during dinner times....
The accompanying data are​ drive-through service times​ (seconds) recorded at a fast-food restaurant during dinner times. Assuming that dinner service times at the​ restaurant's competitor have standard deviation σ = 61.4​sec, use a 0.01 significance level to test the claim that service times at the restaurant have the same variation as service times at its​ competitor's restaurant. Use the accompanying data to identify the null​ hypothesis, alternative​ hypothesis, test​ statistic, and​ P-value. Then state a conclusion about the null hypothesis....
The accompanying data are​ drive-through service times​(seconds) recorded at a fast-food restaurant during dinner times. Assuming...
The accompanying data are​ drive-through service times​(seconds) recorded at a fast-food restaurant during dinner times. Assuming that dinner service times at the​ restaurant's competitor have standard deviation σ = 61.4​sec, use a 0.01 significance level to test the claim that service times at the restaurant have the same variation as service times at its​ competitor's restaurant. Use the accompanying data to identify the null​ hypothesis, alternative​ hypothesis, test​ statistic, and​ P-value. Then state a conclusion about the null hypothesis. Need...
The accompanying data are​ drive-through service times​ (seconds) recorded at a fast food restaurant during dinner...
The accompanying data are​ drive-through service times​ (seconds) recorded at a fast food restaurant during dinner times. Assuming that dinner service times at the​restaurant's competitor have standard deviation σ=58.8 ​sec, use a 0.025 significance level to test the claim that service times at the restaurant have the same variation as service times at its​ competitor's restaurant. 192 160 138 81 159 199 151 113 189 161 176 195 295 165 263 161 233 158 107 195 146 333 218 235...
Accuracy of Fast Food Drive-Through Orders In a study of Burger King drive-through orders, it was...
Accuracy of Fast Food Drive-Through Orders In a study of Burger King drive-through orders, it was found that 264 orders were accurate and 54 were not accurate. For McDonald’s, 329 orders were found to be accurate while 33 orders were not accurate (based on data from QSR magazine). Use a 0.05 significance level to test the claim that Burger King and McDonald’s have the same accuracy rates.
Pop-In Burgers owns numerous restaurants and food production facilities. The company routinely evaluates proposals to drive...
Pop-In Burgers owns numerous restaurants and food production facilities. The company routinely evaluates proposals to drive operational efficiency. Four such proposals are currently under review. One entails the suggestion to close the unprofitable store in Canyon City. Another is to outsource the acquisition of onions, rather than growing them. Another proposal is to sell packaged beef to a non-competing restaurant chain under a private label. The final proposal is to scrap packaging material that is printed with an old logo....
A large national survey shows that the waiting times for fast food restaurants is approximately normally...
A large national survey shows that the waiting times for fast food restaurants is approximately normally distributed with a mean of μ = 3.4 minutes and a standard deviation of σ = 0.6 minutes. A fast food outlet claims that their mean waiting time in line is less than 3.4 minutes. To test the claim, a random sample of 60 customers is selected, and is found to have a mean of 3.3 minutes Use this sample data to test the...
A large national survey shows that the waiting times for fast food restaurants is approximately normally...
A large national survey shows that the waiting times for fast food restaurants is approximately normally distributed with a mean of μ = 3.4 minutes and a standard deviation of σ = 0.6 minutes. A fast food outlet claims that their mean waiting time in line is less than 3.4 minutes. To test the claim, a random sample of 60 customers ia selected, and is found to have a mean of 3.3 minutes Use this sample data to test the...
Many fast-food restaurants use automatic soft-drink dispensing machines that fill cups once an order is placed at a drive-through window.
Many fast-food restaurants use automatic soft-drink dispensing machines that fill cups once an order is placed at a drive-through window. A regional manager for a fast-food chain wants to determine if the machines in her region are dispensing the same amount of product. She samples four different machines and measures a random sample of 16-ounce drinks from each machine. Here is the data she collects (in ounces): Machine 1 Machine 2 Machine 3 Machine 4 16.5 15.0 16.0 16.6 16.6...
Fast food franchises considering a drive up window food service operation. assume that cars arrive at...
Fast food franchises considering a drive up window food service operation. assume that cars arrive at the service following a position distribution at a rate of 24 customers per hour. assume that the service distribution is exponential arriving customers place orders on an intercom station at the back of the parking lot and then drive to the service window to pick up their orders and pay for the service. the situation can be implemented using a single server operation for...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT