(1)125×3.2(2)4×6.2×2.5(3)12.8×9.9(4)10.1×4.8-0.48(5)24÷16(6)15-3.8-6.2
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解:(1)125×3.2,
=125×8×0.4,
=1000×0.4,
=400;
(2)4×6.2×2.5,
=4×2.5×6.2,
=10×6.2,
=62;
(3)12.8×9.9,
=12.8×(10-0.1),
=128-1.28,
=126.72;
(4)10.1×4.8-0.48,
=101×0.48-0.48,
=(101-1)×0.48,
=100×0.48,
=48;
(5)24÷16,
=24÷(4×4)
=24÷4÷4,
=6÷4,
=1.5;
(6)15-3.8-6.2,
=15-(3.8+6.2),
=15-10,
=5.
解析分析:(1)把3.2看作8×0.4,运用乘法结合律简算;(2)运用乘法交换律与结合律简算;(3)把9.9看作10-0.1,运用乘法结合律简算;(4)原式变为101×0.48-0.48,运用乘法结合律简算;(5)把16看作4×4,运用除法的性质简算;(6)运用减法的性质简算.
点评:完成本题要注意分析式中数据,运用合适的简便方法计算.