125×9642.7-45.27-2.725×201317×17-17×17125×1613.7+0.98+0.02+4.340-12.85-2.1599×324+32499×7548.14-2.43-5.57+2.8614×25×3×425.43-(5.43+12.5)
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解:(1)125×96,
=125×8×12,
=1000×12,
=12000;
(2)42.7-45.27-2.7,
=(42.7-2.7)-45.27,
=40-45.27,
=-5.27;
(3)25×201,
=25×(200+1),
=25×200+25×1,
=5000+25,
=5025;
(4)317×17-17×17,
=(317-17)×17,
=300×17,
=5100;
(5)125×16,
=125×8×2,
=1000×2,
=2000;
(6)13.7+0.98+0.02+4.3,
=(13.7+4.3)+(0.98+0.02),
=18+1,
=19;
(7)40-12.85-2.15,
=40-(12.85+2.15),
=40-15,
=25;
(8)99×324+324,
=(99+1)×324,
=100×324,
=32400;
(9)99×75,
=(100-1)×75,
=100×75-1×75,
=7500-75,
=7425;
(10)48.14-2.43-5.57+2.86,
=(48.14+2.86)-(2.43+5.57),
=51-8,
=43;
(11)14×25×3×4,
=(14×3)×(25×4),
=42×100,
=4200;
(12)25.43-(5.43+12.5),
=25.43-5.43-12.5,
=20-12.5,
=7.5.
解析分析:(1)先把96分解成8×12,再运用乘法结合律简算;
(2)运用加法交换律简算;
(3)把201分解成200+1,再运用乘法分配律简算;
(4)(8)运用乘法分配律简算;
(5)把16分解成8×2,再运用乘法结合律简算;
(6)(10)运用加法结合律简算;
(7)(12)根据连续减去两个数等于减去这两个数的和简算;
(9)把99分解成100-1,再运用乘法分配律简算;
(11)运用乘法结合律简算.
点评:此题是考查四则混合运算,要仔细观察算式的特点,灵活运用一些定律进行简便计算.