# Stats

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A random sample of 30 women drank an average of 15 cups of coffee per week during examination finals,
with the sample standard deviation equal to 3 cups. A upper limit of an approximate confidence interval
with 95% of the population average cup drunk is ?

• Stats -

95% confidence interval = μ ± 1.96 SE

Standard Error (SE) = SD/√(n-1)

Z = (x-μ)/SE

1.96 = (x-15)/SE

Solve for x.

I hope this helps.

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