Mann-Whitney Test Ranks Sum of mother's educ revised N Mean Rank Ranks math courses taken HS grad or less 46 28.99 1333.50 Some College 18 41.47 746.50 Total 64 Test Statistics math courses taken Mann-Whitney U 252.500 Wilcoxon W 1333.500 Z -2.477 Asymp. Sig. (2-tailed) .013 a. Grouping Variable: mother's educ revised