A school administrator wants to see if there is a difference in the number of students per class for PortlandPublic School district (group 1) compared to the Beaverton School district (group 2). Assume thepopulations are normally distributed with unequal variances. A random sample of 26 Portland classes founda mean of 35 students per class with a standard deviation of 2. A random sample of 28 Beaverton classesfound a mean of 32 students per class with a standard deviation of 4.Find a 90% confidence interval in the difference of the means. Round answers to 4 decimal places.<μ1-f₂<

Public School district Sample size, n1=26 Sample mean, x¯1=35 Sample sd, s1=2 Beaverton School…

Answered: A school administrator wants to see if…

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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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 11 days following no advertisements, the mean was 16.6 purchasing customers with a standard deviation of 1.1 customers. On 10 days following advertising, the mean was 17.7 purchasing customers with a standard deviation of 1.4 customers. Test the claim, at the 0.02 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 2 of 3 : Compute…
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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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