Null hypothesis: ? <= 29
Alternative hypothesis: ? > 29
Note that these hypotheses constitute a one-tailed test. The null hypothesis will be rejected if the sample mean is too small.SE = s / sqrt(n) = 6.2 / sqrt(20) = 1.38636
DF = n - 1 = 20 - 1 = 19
t = (x - ?) / SE = (31 - 29)/1.38636 = 1.4426267
where s is the standard deviation of the sample, x is the sample mean, ? is the hypothesized population mean, and n is the sample size.
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