3.2×0.54=1.728 3.45×0.25=0.8625 1.76×4.2≈7.39 64.8÷24=2.7 验算：
3.2×0.54＝ 0.5 4 × 3.2___________ 1 0 81 6 2___________1 7 2 8
0.54
ⅹ3.2
1080
162
1.728
