(5.6×8.9-5.6×0.9)×1.25=[(5.6×(8.9-0.9)]×1.25=[5.6×8]×1.25=5.6×（8×1.25）=5.6×10=56
(5.6×8.9-5.6×0.9)×1.25=5.6×（8.9-0.9)×1.25=5.6×8×1.25=5.6×（8×1.25）=5.6×10=56
