Confidence intervals and sample size

Reference no: EM131008874

A confidence interval for the price of gasoline from a random sample of 30 gas stations in a region gives the following statistics:

y = $4.49 s = $0.29

a) Find a 95% confidence interval for the mean price of regular gasoline in that region.

b) Find the 90% confidence interval for the mean.

c) If we had the same statistics from a sample of 60 sta- tions, what would the 95% confidence interval be now?

Reference no: EM131008874

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