A researcher believes that community B has a lower income than
community A. Forty people are surveyed in each of the two
communities regarding their income. In place A, the mean among the
40 individuals is 62 (given in thousands; you can ignore the
‘thousands’ and just use ‘61’), and the variance is 95; in place B,
the mean among the 40 surveyed is 59, and the variance is
100. Test the null hypothesis that the two communities
have equal...