三、计算下面各题，怎样简便就怎样计算。（每题 4 分，共 40 分）
31 - 24.5÷3.5 + 0.68 48.4 + 2.78 + 51.6 - 0.48
6.5×1.4 - 24.96÷7.8 1000÷32÷0.25÷1.25
5.85×8.9 + 11×0.585 9.05 - 0.736÷(2.3×0.4)
35 - (6.32 - 2.64)÷0.23 46.7 - (6.7 + 6.86÷0.7)
19.35÷0.18÷4.3 - 5.9 8.5×[3.64÷(7.1 - 1.9)]

31 - 24.5÷3.5 + 0.68
= 31 - 7 + 0.68
= 24 + 0.68
= 24.68
48.4 + 2.78 + 51.6 - 0.48
= (48.4 + 51.6) + (2.78 - 0.48)
= 100 + 2.3
= 102.3
6.5×1.4 - 24.96÷7.8
= 9.1 - 3.2
= 5.9
1000÷32÷0.25÷1.25
= 1000÷(32×0.25×1.25)
= 1000÷(8×4×0.25×1.25)
= 1000÷[(8×1.25)×(4×0.25)]
= 1000÷(10×1)
= 1000÷10
= 100
5.85×8.9 + 11×0.585
= 5.85×8.9 + 1.1×5.85
= 5.85×(8.9 + 1.1)
= 5.85×10
= 58.5
9.05 - 0.736÷(2.3×0.4)
= 9.05 - 0.736÷0.92
= 9.05 - 0.8
= 8.25
35 - (6.32 - 2.64)÷0.23
= 35 - 3.68÷0.23
= 35 - 16
= 19
46.7 - (6.7 + 6.86÷0.7)
= 46.7 - (6.7 + 9.8)
= 46.7 - 16.5
= 30.2
19.35÷0.18÷4.3 - 5.9
= 107.5÷4.3 - 5.9
= 25 - 5.9
= 19.1
8.5×[3.64÷(7.1 - 1.9)]
= 8.5×[3.64÷5.2]
= 8.5×0.7
= 5.95

31 - 24.5÷3.5 + 0.68
= 31 - 7 + 0.68
= 24 + 0.68
= 24.68
48.4 + 2.78 + 51.6 - 0.48
= (48.4 + 51.6) + (2.78 - 0.48)
= 100 + 2.3
= 102.3
6.5×1.4 - 24.96÷7.8
= 9.1 - 3.2
= 5.9
1000÷32÷0.25÷1.25
= 1000÷(32×0.25×1.25)
= 1000÷(8×4×0.25×1.25)
= 1000÷[(8×1.25)×(4×0.25)]
= 1000÷(10×1)
= 1000÷10
= 100
5.85×8.9 + 11×0.585
= 5.85×8.9 + 1.1×5.85
= 5.85×(8.9 + 1.1)
= 5.85×10
= 58.5
9.05 - 0.736÷(2.3×0.4)
= 9.05 - 0.736÷0.92
= 9.05 - 0.8
= 8.25
35 - (6.32 - 2.64)÷0.23
= 35 - 3.68÷0.23
= 35 - 16
= 19
46.7 - (6.7 + 6.86÷0.7)
= 46.7 - (6.7 + 9.8)
= 46.7 - 16.5
= 30.2
19.35÷0.18÷4.3 - 5.9
= 107.5÷4.3 - 5.9
= 25 - 5.9
= 19.1
8.5×[3.64÷(7.1 - 1.9)]
= 8.5×[3.64÷5.2]
= 8.5×0.7
= 5.95