28.67×67+3.2×286.7+573.4×0.05=28.67 * 67 + 28.67 * 10 * 3.2 + 28.67 * 20 * 0.05 = 28.67 (67 + 32 + 1) =28.67 *100 = 2867
(思路：我看这题时,看到了28.67 ,286.7 ,573.4 它们分别存在10倍,20倍关系)weishema