# math

A study of 60 bolts of carpet showed that their average length was 180 yards. The standard deviation of the population is 6 yards. Which of the following is the 99% confidence interval for the mean length per bolt of carpet?

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1. No alternatives given. Cannot copy and paste here.

99% = mean ± 2.575 SEm

SEm = SD/√n

You do the math.

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