您现在的位置是:首页 > 学科知识查询 > 小学数学题库

计算下面各题. 420÷[×4] 9×÷12 99×45 47×15+43×15 14×36+14×63+14 45×8×25 125×32×25 ×4

编辑:chaxungu时间:2026-04-27 13:21:26分类:小学数学题库

计算下面各题(能简便的必须简便计算)。
420÷[(205-198)×4]9×(16+60)÷1299×4547×15+43×15
14×36+14×63+1445×8×25125×32×25(25+20)×4
解:(1)420÷[(205-198)×4],
=420÷[7×4],
=420÷28,
=15;
(2)9×(16+60)÷12,
=9×76÷12,
=684÷12,
=57;
(3)99×45,
=(100-1)×45,
=100×45-45×1,
=4500-45,
=4455;
(4)47×15+43×15,
=(47+43)×15,
=90×15,
=1350;
(5)14×36+14×63+14,
=14×(36+63+1),
=14×100,
=1400;
(6)45×8×25,
=45×2×4×25,
=(45×2)×(4×25),
=90×100,
=9000;
(7)125×32×25,
=125×8×4×25,
=(125×8)×(4×25),
=1000×100,
=100000;
(8)(25+20)×4,
=25×4+20×4,
=100+80,
=180