1234567×3456789的简便计算方法,浙大提前招题,太坑爹了
来源:学生作业帮 编辑:百度作业网作业帮 分类:数学作业 时间:2024/06/15 22:49:10
1234567×3456789的简便计算方法,浙大提前招题,太坑爹了
![1234567×3456789的简便计算方法,浙大提前招题,太坑爹了](/uploads/image/z/17967220-52-0.jpg?t=1234567%C3%973456789%E7%9A%84%E7%AE%80%E4%BE%BF%E8%AE%A1%E7%AE%97%E6%96%B9%E6%B3%95%2C%E6%B5%99%E5%A4%A7%E6%8F%90%E5%89%8D%E6%8B%9B%E9%A2%98%2C%E5%A4%AA%E5%9D%91%E7%88%B9%E4%BA%86)
1234567*3456789=(1234567.9-0.9)*3456789
=1234567.9*3456789-0.9*(123456790-120000000-1)
=12345679*345678.9-12345679*9+108000000+0.9
=12345679*345669.9+0.9+108000000
=12345679*9*(38408-7/30)+0.9+108000000
=111111111*38408-111111111*7/30+0.9+108000000
=111111111*38408-25925925+108000000
=3333333330000+
888888888000+
44444444400+
888888888+
108000000-25925925
=4267663551288-
25925925
=4267637625363
其实我觉得还是笔算比较快.
=1234567.9*3456789-0.9*(123456790-120000000-1)
=12345679*345678.9-12345679*9+108000000+0.9
=12345679*345669.9+0.9+108000000
=12345679*9*(38408-7/30)+0.9+108000000
=111111111*38408-111111111*7/30+0.9+108000000
=111111111*38408-25925925+108000000
=3333333330000+
888888888000+
44444444400+
888888888+
108000000-25925925
=4267663551288-
25925925
=4267637625363
其实我觉得还是笔算比较快.