Question

口算下面各題． 5-0.64=	0.8+12.2=	0.2×0.3=	0.63÷0.9=
2.7+7.3=	10×0.45=	0.21×2=	0.75÷0.25=
0.7+2.8=	7.3-0.6=	0.84÷0.2=	0.12×0=
0.4×0.05=	0.5÷100=	5.2+3.8=	1.45+5.5=

Answer 1

分析：根據(jù)小數(shù)加減乘除法的計算方法進(jìn)行計算．

解答：解：

5-0.64=4.36	0.8+12.2=13	0.2×0.3=0.06	0.63÷0.9=0.7
2.7+7.3=10	10×0.45=4.5	0.21×2=0.42	0.75÷0.25=3
0.7+2.8=3.5	7.3-0.6=6.7	0.84÷0.2=4.2	0.12×0=0
0.4×0.05=0.02	0.5÷100=0.005	5.2+3.8=9	1.45+5.5=6.95．

點(diǎn)評：口算時，注意運(yùn)算符號和數(shù)據(jù)，然后再進(jìn)一步計算．