Question

125*8.9*0.8 2.08*99+2.08 6.8-2.78-0.22 1.6/0.25/4 5.7-1.9*0.2/7.6 3.2*【2.1+1.95/6.5】

【想怎样简便就怎样简便】

Answer 1

125*8.9*0.8
=（125*0.8）*8.9
=100*8.9=890
2.08*99+2.08
=2.08*（99+1）
=2.08*100
=208
6.8-2.78-0.22
=6.8-(2.78+0.22)
=6.8-3
=3.8
1.6/0.25/4
=
=1.6/(0.25*4)
=1.6/1
=1.6
5.7-1.9*0.2/7.6
=5.7-1.9*0.2*10/76
=5.7-0.38*10/76
=5.7-3.8/76
=5.7-0.05
=5.65
3.2*【2.1+1.95/6.5】
=3.2*(2.1+0.3)
=3.2*2.4
=7.68

Answer 2

125*8.9*0.8
=(125*0.8)*8.9
=100*8.9
=890

2.08*99+2.08
=2.08*(99+1)
=2.08*100
=208

6.8-2.78-0.22
=6.8-(2.78+0.22)
=6.8-3
=3.8

1.6÷0.25÷4
＝1.6÷（0.25×4）
＝1.6÷1
＝1.6

5.7-1.9*0.2/7.6
=5.7-0.38/7.6
=5.7-38/760
=5.7-1/20
=5.7-0.05
=5.65

3.2*[2.1+1.95/6.5]
=3.2*(2.1+0.3)
=3.2*2.4
=3.2*(2+0.4)
=3.2*2+3.2*0.4
=6.4+1.28
=7.68

Answer 3

125×8.9×0.8
＝125×0.8×8.9
＝100×8.9
＝890
2.08×99+2.08
＝2.08×（99+1）
＝2.08×100
＝208
6.8-2.78-0.22
＝6.8-（2.78+0.22）
＝6.8-3
＝3.8
1.6÷0.25÷4
＝1.6÷（0.25×4）
＝1.6÷1
＝1.6
5.7-1.9×0.2÷7.6
＝5.7-0.05
＝5.65
3.2×[2.1+1.95÷6.5]
＝3.2×[2.1+0.3]
＝3.2×2.4
＝7.68