Question

列豎式計(jì)算
12.58+7.64=
78.5-12.56=
0.843×1.23=
54.81÷0.09=

Answer 1

分析：①②運(yùn)用小數(shù)的乘除法的計(jì)算法則進(jìn)行計(jì)算即可．注意小數(shù)點(diǎn)對(duì)齊．
③按這整數(shù)乘法的方法進(jìn)行計(jì)算，再看因數(shù)中一共有幾位小數(shù)，就從積的末尾起數(shù)出幾位點(diǎn)上小數(shù)點(diǎn)．
④先把除數(shù)的小數(shù)點(diǎn)向右移動(dòng)一位，使它變成整數(shù)，除數(shù)的小數(shù)點(diǎn)向右移動(dòng)幾位，被除數(shù)的小數(shù)點(diǎn)也向右移動(dòng)相同的位數(shù)，然后按著除數(shù)是整數(shù)方法進(jìn)行計(jì)算．

解答：解：12.58+7.64=20.22；

78.5-12.56=65.94；

0.843×1.23=1.03689；

54.81÷0.09=609．

點(diǎn)評(píng)：本題運(yùn)用小數(shù)加減、乘除法的計(jì)算法則進(jìn)行計(jì)算即可．