Solution :
t /2,df = 1.984
Margin of error = E = t/2,df * (s /n)
= 1.984 * 0.02
Margin of error = E = 0.04
The 95% confidence interval estimate of the population mean is,
- E < < + E
3.2 - 0.04 < < 3.2 + 0.04
3.16 < < 3.24
(3.16 , 3.24)
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