3.2×4.5＋32×0.55－0.32……… 变一变，就简便。=3.2×4.5＋3.2×5.5－0.32=3.2×（4.5＋5.5）－0.32=3.2×10－0.32=32－0.32=31.68
0.375X48-0.125X24=（0.75-0.125）X24=0.625X24=15
