急求简便运算方法!Thank you!18.7×28-8.7×28 ﹙1.25+2.5﹚×8 101×101-101 19.8+86.43+20.2+57%25%×76-0.25×46+四分之一×70 八分之五×99+八分之五 七分之五×七分之三+七分之四÷五分之七 9.9+99.9
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/15 09:06:22
![急求简便运算方法!Thank you!18.7×28-8.7×28 ﹙1.25+2.5﹚×8 101×101-101 19.8+86.43+20.2+57%25%×76-0.25×46+四分之一×70 八分之五×99+八分之五 七分之五×七分之三+七分之四÷五分之七 9.9+99.9](/uploads/image/z/609016-40-6.jpg?t=%E6%80%A5%E6%B1%82%E7%AE%80%E4%BE%BF%E8%BF%90%E7%AE%97%E6%96%B9%E6%B3%95%21Thank+you%2118.7%C3%9728-8.7%C3%9728+%EF%B9%991.25%EF%BC%8B2.5%EF%B9%9A%C3%978+101%C3%97101%EF%BC%8D101+19.8%EF%BC%8B86.43%EF%BC%8B20.2%EF%BC%8B57%2525%25%C3%9776%EF%BC%8D0.25%C3%9746%EF%BC%8B%E5%9B%9B%E5%88%86%E4%B9%8B%E4%B8%80%C3%9770+%E5%85%AB%E5%88%86%E4%B9%8B%E4%BA%94%C3%9799%EF%BC%8B%E5%85%AB%E5%88%86%E4%B9%8B%E4%BA%94+%E4%B8%83%E5%88%86%E4%B9%8B%E4%BA%94%C3%97%E4%B8%83%E5%88%86%E4%B9%8B%E4%B8%89%EF%BC%8B%E4%B8%83%E5%88%86%E4%B9%8B%E5%9B%9B%C3%B7%E4%BA%94%E5%88%86%E4%B9%8B%E4%B8%83+9.9%EF%BC%8B99.9)
急求简便运算方法!Thank you!18.7×28-8.7×28 ﹙1.25+2.5﹚×8 101×101-101 19.8+86.43+20.2+57%25%×76-0.25×46+四分之一×70 八分之五×99+八分之五 七分之五×七分之三+七分之四÷五分之七 9.9+99.9
急求简便运算方法!Thank you!18.7×28-8.7×28 ﹙1.25+2.5﹚×8 101×101-101 19.8+86.43+20.2+57%
25%×76-0.25×46+四分之一×70 八分之五×99+八分之五
七分之五×七分之三+七分之四÷五分之七 9.9+99.9+999.99+0.3
急求简便运算方法!Thank you!18.7×28-8.7×28 ﹙1.25+2.5﹚×8 101×101-101 19.8+86.43+20.2+57%25%×76-0.25×46+四分之一×70 八分之五×99+八分之五 七分之五×七分之三+七分之四÷五分之七 9.9+99.9
1 =(18.7-8.7)x28=10x28=280
2 =1.25x8+2.5x8=10+20=30
3 =101x(101-1)=101x100=10100
4 打错(57应为.57吧)结合律
5 =0.25x(76-46+70)=0.25x100=25
6 =5/8x(99+1)=5/8x100=125/2
7 =5/7x3/7+4/7x5/7=5/7x(3/7+4/7)=5/7x1=5/7
8 =(9.9+0.1)+(99.9+0.1)+(999.9+0.1)=10+100+1000=1110