In a retail store, a sample of 36 customers had an average age of 38.7 years...

In a retail store, a sample of 36 customers had an average age of 38.7 years and standard deviation is 12.5. A retail store owner claims that the average age of their customers is less than 40 years old. Test this claim at = 0.05 .

i want a clear answer ‏please

Expert Solution

by using the following Students "t"distribution table we got the t value

orchestra answered 2 years ago

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