用简便方法计算．1.25×4×2.5×0.88.08×1.252.5×（40－－0.4）99×0.453.7×4.3＋3.7×1.2＋3.7×4.5．
方法
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| 用简便方法计算． 1.25×4×2.5×0.8 8.08×1.25 2.5×（40--0.4） 99×0.45 3.7×4.3+3.7×1.2+3.7×4.5． |
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（1）1.25×4×2.5×0.8
=（1.25×0.8）×（4×2.5）
=1×10
=10；（2）8.08×1.25
=（8+0.08）×1.25
=8×1.25+0.08×1.25
=10+0.1
=10.1；（3）2.5×（40-0.4）
=2.5×40-2.5×0.4
=100-10
=90；（4）99×0.45
=（100-1）×0.45
=100×0.45-0.45
=45-0.45
=44.55；（5）3.7×4.3+3.7×1.2+3.7×4.5
=3.7×（4.3+1.2+4.5）
=3.7×10
=37．