Question

脫式計算數(shù)我棒．
12.8+2.04×9.5                      
0.6×（4.2-0.8）-0.45
3.2×1.4+5.62                           
51.8-4.8×（2.03-0.18）

Answer 1

分析：根據(jù)小數(shù)四則混合運(yùn)算的運(yùn)算順序：先算乘除、后算加減，有括號的先算括號的；據(jù)此依次進(jìn)行解答即可．

解答：解：12.8+2.04×9.5
=12.8+19.38
=32.18

0.6×（4.2-0.8）-0.45
=0.6×3.4-0.45
=2.04-0.45
=1.59

3.2×1.4+5.62
=4.48+5.62
=10.1

51.8-4.8×（2.03-0.18）
=51.8-4.8×1.85
=51.8-8.88
=42.92．

點評：此題主要考查小數(shù)的四則混合運(yùn)算的運(yùn)算順序，然后再進(jìn)一步計算．