Question

列豎式計(jì)算．
78.6×2.5=
1.25÷0.25=
19.76÷5.2=

Answer 1

考點(diǎn)：小數(shù)乘法,小數(shù)除法

專題：常規(guī)題型

分析：（1）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)．
（2）先把除數(shù)的小數(shù)點(diǎn)向右移動一位，使它變成整數(shù)，除數(shù)的小數(shù)點(diǎn)向右移動幾位，被除數(shù)的小數(shù)點(diǎn)也向右移動相同的位數(shù)，然后按著除數(shù)是整數(shù)方法進(jìn)行計(jì)算．

解答： 解：78.6×2.5=196.5

1.25÷0.25=5

19.76÷5.2=3.8

點(diǎn)評：此題考查小數(shù)乘法，小數(shù)除法，小數(shù)乘法按整數(shù)乘法法則計(jì)算；小數(shù)除法，先移動除數(shù)的小數(shù)點(diǎn)使它變成整數(shù)，然后按除數(shù)是整數(shù)除法計(jì)算．