发布网友 发布时间:2024-10-24 00:21
共1个回答
热心网友 时间:2024-10-30 10:07
(1)54×303,
=54×(300+3),
=54×300+54×3,
=16200+162,
=16362;
(2)7.7×0.73,
=(7+0.7)×0.73,
=7×0.73+0.7×0.73,
=5.11+0.511,
=5.621;
(3)26.39×36+2.639×830-263.9×1.9,
=26.39×36+26.39×83-26.39×19,
=26.39×(36+83-19),
=26.39×100,
=2639;
(4)272.4×6.2+2724×0.38,
=272.4×6.2+272.4×3.8,
=272.4×(6.2+3.8),
=272.4×10,
=2724;
(5)2.04×0.25×7.2×12.5,
=[(2+0.04)×0.25]×(9×0.8×12.5),
=[2×0.25+0.04×0.25]×[9×(0.8×12.5)],
=[0.5+0.01]×[9×10],
=0.51×90,
=45.9.