Question

Sofi is from Mexico and is looking at flights. She wants to estimate the average cost of a flight to Quer´etaro (where she’s from) with a 95% confidence interval, with a margin of error of $26. She assumes that the standard deviation of flight costs is $45. How many flights should she look at in order to construct the confidence interval?

a. 12 b. 11 c. 299 d. 300

Answer #1

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