Question

求简便计算

3.6x0.81+0.36x1.9 4.05/［1.8x〈3.36-2.86〉］
注：请只用小括号和中括号，只用分配律、交换律和结合律。用简便计算，用梯等式

Answer 1

3.6x0.81+0.36x1.9
=0.36x8.1+0.36x1.9
=0.36*（8.1+1.9）
=3.6
4.05/［1.8x〈3.36-2.86〉］
=4.05/（1.8*0.5）
=8.1/1.8
=9/2
=4.5

Answer 2

3.6x0.81+0.36x1.9
0.36(8.1+1.9)
3.6

4.05/［1.8x〈3.36-2.86〉］
4.05/1.8x0.5
4.05x2/1.8
4.05/0.9
=4.5

Answer 3

3.6x0.81+0.36x1.9=3.6x0.81+3.6x0.19=3.6×（0.81+0.19）=3.6
4.05/［1.8x〈3.36-2.86〉］=4.05/［1.8x0.5］=8.1/1.8=4.5

追问

梯等式

追答

3.6x0.81+0.36x1.9
=3.6x0.81+3.6x0.19
=3.6×（0.81+0.19）
=3.6

4.05/［1.8x〈3.36-2.86〉］
=4.05/［1.8x0.5］
=8.1/1.8
=4.5

Answer 4

9999x1111+3333x667=3333×3×1111＋3333×667 ＝3333×(3333＋667)＝3333×4000＝13332000 19.98x37-199.8x1.9+1998x0.82=19.98×37－19.88×

追问

梯等式