Question

11．直接寫(xiě)得數(shù)

2×0.8=	2.5×8=	6.2+0.04=	2.5×4=	0.6×0.7=
6-0.7=	6.4+4.6=	0.04×0.3=	2.4×5=	2.1-2.01=

Answer 1

分析 計(jì)算小數(shù)加、減法：先把各數(shù)的小數(shù)點(diǎn)對(duì)齊，再按照整數(shù)加、減法的法則進(jìn)行計(jì)算，最后在得數(shù)里對(duì)齊橫線上的小數(shù)點(diǎn)點(diǎn)上小數(shù)點(diǎn)．
計(jì)算小數(shù)乘法按整數(shù)乘法的法則算出積； 再看因數(shù)中一共有幾位小數(shù)，就從得數(shù)的右邊起數(shù)出幾位，點(diǎn)上小數(shù)點(diǎn)．得數(shù)的小數(shù)部分末尾有0，一般要把0去掉．

解答 解：

2×0.8=1.6	2.5×8=20	6.2+0.04=6.24	2.5×4=10	0.6×0.7=0.42
6-0.7=5.3	6.4+4.6=11	0.04×0.3=0.012	2.4×5=12	2.1-2.01=0.09

點(diǎn)評(píng) 本題主要考查了學(xué)生小數(shù)乘法和加減法的計(jì)算能力．