Question

脱式计算（能简算的应该简算）2.8×3.6+1.4×2.8 4.536÷4÷0.25 ...

脱式计算（能简算的应该简算）2.8×3.6+1.4×2.8 4.536÷4÷0.25 9.9+9.9×996.3×10.1 3.6×1.9+0.36×81 15.58÷8.2-0.72．

Answer 1

（1）2.8×3.6+1.4×2.8 
=2.8×（3.6+1.4）
=2.8×5
=14

（2）4.536÷4÷0.25
=4.536÷（4×0.25）
=4.536÷1
=4.536

（3）9.9+9.9×99
=9.9×（1+99）
=9.9×100
=990

（4）6.3×10.1
=6.3×（10+0.1）
=6.3×10+6.3×0.1
=63+0.63
=63.63

（5）3.6×1.9+0.36×81
=3.6×1.9+3.6×8.1
=3.6×（1.9+8.1）
=3.6×10
=36

（6）15.58÷8.2-0.72
=1.9-0.72
=1.18