The daily sales (X) were recorded every day for the past 2 years. Historically, they follow...

 

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The daily sales (X) were recorded every day for the past 2 years. Historically, they follow a Normal distribution with a mean of $200 and a known population standard deviation of $20. Periodically, the store owner likes to take a sample of n-30 days and calculate the sample mean to determine if daily sales have changed away from their trend. a) What is the probability that sales are less than $192. It is Suppose that a sampling of sales during Nov 2021 found the sample mean sales to be $195, Use a hypothesis test to see if average daily sales are now significantly lower than the historical average of $200 at a 10%. b) Calculate the p-value. The p-value is c) Is there evidence supporting the alternative hypothesis? Yes-1 and No-0. The answer is The daily sales (X) were recorded every day for the past 2 years. Historically, they follow a Normal distribution with a mean of $200 and a known population standard deviation of $20. Periodically, the store owner likes to take a sample of n-30 days and calculate the sample mean to determine if daily sales have changed away from their trend. a) What is the probability that sales are less than $192. It is Suppose that a sampling of sales during Nov 2021 found the sample mean sales to be $195, Use a hypothesis test to see if average daily sales are now significantly lower than the historical average of $200 at a 10%. b) Calculate the p-value. The p-value is c) Is there evidence supporting the alternative hypothesis? Yes-1 and No-0. The answer is

Answer rating: 100% (QA)

a To find the probability that sales are less than 192 we can use the standard normal distribution First we need to calculate the zscore z x where x i... View the full answer