(2)期望值准则 教学建模‘Åûü. ‘ÅÑÖXÚ ºxûü¯K Ø(½.ûü £2¤ Ï"ŠOK ˆ‡YÂÊÏ"ŠŠûüâ§¡Ï"ŠO K" E(A1) = 4 × 0.3 + 5 × 0.5 + 1 × 0.3 = 4.0 E(A2) = 6 × 0.3 + 4 × 0.5 + 1.5 × 0.3 = 4.25 E(A3) = 7 × 0.3 + 2 × 0.5 + 1.2 × 0.3 = 3.46 Ï"ŠOK§ÀJ A2£¯/¤ I‰EŒÆ êÆï