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Please explain fully, using Excel when necessary. These questions were addressed once already, but they were not explained in a way in which they could be fully understood. Please detail each step.

1) A publisher is considering three different covers for a new magazine. A random sample of 90 people are asked to pick their favorite. 20 people selected cover A, 30 people liked cover B, and 40 people prefers cover C, can you conclude at 0.05 significance level the magazine covers are not equal attractive ?

Ho------------------- H1----------------------

a = 0.05; Critical value= --------

Decision rule ------------------

Test statistic (or p-value)? Decision and interpretation ?

Problem 2) The mean annual sales of a company in 36 of its department stores around the country (They have over 1500 stores.) Is $23,860.000 with Standard deviation of $2,150,000 A manager quotes the annual sales of her store to be 25,000,000. Does the sample data provide evidence to reject the manager's claim at a significance level of 0.01?

Ho----------------- H1-----------------

a = 0.01; Critical value = -----------

Decision Rule-----------------

Test Statistic (or p-value)? Decision and interpretation?

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Please explain the statistic problems fully, using Excel when necessary. These questions were addressed once already, but they were not explained in a way in which they could be fully understood. Please detail each step.

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Please explain fully, using Excel when necesary. These questions were addressed once already, but they were not explained in a way in which they could be fully understood. Please detail each step. Thanks!

1)A publisher is considering three different covers for a new magazine. A random sample of 90 people are asked to pick their favorite. 20 people selected cover A, 30 people liked cover B, and 40 people preffers cover C, can you conclude at 0.05 significance level the magazine covers are not equal attractive ?

Ho------------------- H1----------------------

a = 0.05; Critical value= --------

Decision rule ------------------

Test statistic (or p-value)? Decision and interpretation ?

Solution. Denote the proportion ...

###### Education

- BSc , Wuhan Univ. China
- MA, Shandong Univ.

###### Recent Feedback

- "Your solution, looks excellent. I recognize things from previous chapters. I have seen the standard deviation formula you used to get 5.154. I do understand the Central Limit Theorem needs the sample size (n) to be greater than 30, we have 100. I do understand the sample mean(s) of the population will follow a normal distribution, and that CLT states the sample mean of population is the population (mean), we have 143.74. But when and WHY do we use the standard deviation formula where you got 5.154. WHEN & Why use standard deviation of the sample mean. I don't understand, why don't we simply use the "100" I understand that standard deviation is the square root of variance. I do understand that the variance is the square of the differences of each sample data value minus the mean. But somehow, why not use 100, why use standard deviation of sample mean? Please help explain."
- "excellent work"
- "Thank you so much for all of your help!!! I will be posting another assignment. Please let me know (once posted), if the credits I'm offering is enough or you ! Thanks again!"
- "Thank you"
- "Thank you very much for your valuable time and assistance!"

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