Question

2．計算下面各題，能簡算的就簡算．  
0.25×6.82×4
5.52×0.6+8.9
11×7.5-7.5
4.36×0.7+5.64×0.7
3.96÷0.4÷2.5．

Answer 1

分析 ①運用乘法交換律可簡便計算，
②先算乘法再算加法，
③④逆用乘法分配律可簡便計算，
⑤根據除法的性質計算．

解答 解：①0.25×6.82×4
=0.25×4×6.28
=1×6.28
=6.28

②5.52×0.6+8.9
=3.312+8.9
=12.212

③11×7.5-7.5
=（11-1）×7.5
=10×7.5
=75

④4.36×0.7+5.64×0.7
=（4.36+5.64）×0.7
=10×0.7
=7

⑤3.96÷0.4÷2.5
=3.96÷（0.4×2.5）
=3.96÷1
=3.96

點評 此題考查小數四則混合運算順序和靈活運用運算定律，分析數據找到正確的計算方法．