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In: Statistics and Probability

At two different branches of a department store, pollsters randomly sampled 100 customers at store 1...

At two different branches of a department store, pollsters randomly sampled 100 customers at store 1 and 80 customers at store 2, all on the same day. At store 1, the average amount purchased was $41.25 per customer with a sample standard deviation of $24.25. At store 2 the average amount purchased was $45.75 with a sample standard deviation of $34.76.

a) Construct a 95% confidence interval for the mean amount purchased per customer in Store 1 and Store 2.

b) Construct a 95% confidence interval for the difference between the means of purchases per customer of the two stores.

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orchestra answered 2 years ago
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