2.2乘以4.9加17乘以0.66怎么巧算

2.2乘以4.9加17乘以0.66怎么巧算 54乘以45加90乘以23怎么巧算 五年级 0.15乘以0.8乘以12.5加8乘以3乘以0.125怎么简便算 99乘以22加33乘以34怎么简便运算 7.5乘以23加31乘以2.5怎么简算 99乘以22加33乘以34怎么简便运算 怎么简算13.5乘以10.1加6.5乘以9.9 222乘以85加111乘以30怎么简便计算? 123乘以79加369乘以7怎么简便 66乘以0.88加33乘以0.24 怎么简便运算 248乘以66加3788的巧算题怎么算 20乘以20减19乘以19加18乘以18减17乘以17加...加2乘以2减1乘以1的结果 27乘以3.4加15.4乘以34减340乘以百分之81,怎么简算. 0.888乘以125乘以73加999乘以3用简便算法怎么算 5加64乘以25乘以125乘以93怎么简便计算 444乘以16加111乘以36如何巧算 怎样巧算 3333乘以4444加3334乘以2222 7.8乘以4.2加2.2乘以4.2等于(7.8+2.2)乘以4.2这是根据( )简算