The customers at a bank complained about long lines and the time they had to spend waiting for service. It is known that the customersat this bank had to wait 11 minutes, on average, before being served. The management made some changes to reduce the waiting timefor its customers. A sample of 61 customers taken after these changes were made produced a mean waiting time of 10.2 minutes witha standard deviation of 2.9 minutes. Using this sample mean, the bank manager displayed a huge banner inside the bank mentioningthat the mean waiting time for customers has been reduced by new changes. Do you think the bank manager's claim is justifiable? Usea 0.5% significance level to answer this question. Use both approaches.Use the p-value approach. Use the t distribution table to find a range for the p-value. Enter the exact values for the range.

Given that Sample size n = 61 Sample mean = 10.2 Sample SD = 2.9 Level of significance = 0.5% =…

Answered: The customers at a bank complained…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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The customers at a bank complained about long lines and the time they had to spend waiting for service. It is known that the customers at this bank had to wait 11 minutes, on average, before being served. The management made some changes to reduce the waiting time for its customers. A sample of 61 customers taken after these changes were made produced a mean waiting time of 10.2 minutes with a standard deviation of 2.9 minutes. Using this sample mean, the bank manager displayed a huge banner inside the bank mentioning that the mean waiting time for customers has been reduced by new changes. Do you think the bank manager’s claim is justifiable? Use a 0.5% significance level to answer this question. Use both approaches.Use the p-value approach. Use the t distribution table to find a range for the p-value. Enter the exact values for the range.Enter your answer; the range for the p-value, lower bound< p-value <Enter your answer; the range for the p-value, upper boundUse the…
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A new small business wants to know if its current radio advertising is effective. The owners decide to look at the mean number of customers who make a purchase in the store on days immediately following days when the radio ads are played as compared to the mean for those days following days when no radio advertisements are played. They found that for 7 days following no advertisements, the mean was 22.1 purchasing customers with a standard deviation of 1.2 customers. On 10 days following advertising, the mean was 24.1 purchasing customers with a standard deviation of 1.6 customers. Test the claim, at the 0.05 level, that the mean number of customers who make a purchase in the store is lower for days following no advertising compared to days following advertising. Assume that both populations are approximately normal and that the population variances are equal. Let days following no advertisements be Population 1 and let days following advertising be Population 2. Step 1 of 3: State the…
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A new small business wants to know if its current radio advertising is effective. The owners decide to look at the mean number of customers who make a purchase in the store on days immediately following days when the radio ads are played as compared to the mean for those days following days when no radio advertisements are played. They found that for 13 days following no advertisements, the mean was 23.9 purchasing customers with a standard deviation of 1.9 customers. On 6 days following advertising, the mean was 24.7 purchasing customers with a standard deviation of 1.6 customers. Test the claim, at the 0.01 level, that the mean number of customers who make a purchase in the store is lower for days following no advertising compared to days following advertising. Assume that both populations are approximately normal and that the population variances are equal. Let days following no advertisements be Population 1 and let days following advertising be Population 2. Step 3 of 3: Draw a…

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