Question

16．口算

0.6+0.3=	5.3+3.7=	0.6+1.2=	7.6+1.4=
1.2-0.4=	7.9-0.9=	1-0.8=	12.5-2.5=
1.2-0.9=	10-2.5=	8.4+3=	9+0.1=
20-19.8=	1-0.6=	0.39+0.61=	3.9+2.1=

Answer 1

分析 根據(jù)小數(shù)加減法運算的計算法則計算即可求解．

解答 解：

0.6+0.3=0.9	5.3+3.7=9	0.6+1.2=1.8	7.6+1.4=9
1.2-0.4=0.8	7.9-0.9=7	1-0.8=0.2	12.5-2.5=10
1.2-0.9=0.3	10-2.5=7.5	8.4+3=11.4	9+0.1=9.1
20-19.8=0.2	1-0.6=0.4	0.39+0.61=1	3.9+2.1=6

點評 考查了小數(shù)加減法運算，關(guān)鍵是熟練掌握計算法則正確進行計算．