7/11÷9＋1/9×4/11＝7/11×1/9＋1/9×4/11＝1/9×﹙7/11＋4/11﹚＝1/9×1＝1/9，等于9分之14×﹙1/8＋3/4﹚－1/2＝4×1/8＋4×3/4－1/2＝1/2＋3－1/2＝3
