一、直接写出得数.
25 × 4 = 12.5 × 8 = 62 + 48 = 1－10%=
17 ÷ 34 = 4 ÷ = － = 0.4 － =
+ 0.5 = 0.2 ÷ 0.1 = 4.8 × = 7.2 ÷ 0.3 =
100% × 1.8 = × 35 = 0.5 ÷ = 3.02 + 6.8 =
10 － 0.1 = 2.5 × 40 = 24 ÷ 0.8 = 0.1 ÷ 0.01 =
+ = 1 － = ÷ 5 = － =
65 － 56 = 0.9 × 100 = 5.13 + 0.5 = － =
2.5 × 4 = 87 × 10% = 9 － 0.9 = + =
60 ÷ 15 = 12 + 3.2 = 2.8 × = ÷ 4 =
7.2 ÷ 0.3 = ÷ = 45 × = 125 ÷ =
+ = 0 ÷ = × = 7 + =
24 × 5 = 0.5 × 0.8 = 318 ÷ 3 = 4.3 ÷ 0.1 =
二、用简便方法计算.
12.87 － 6.94 － 3.06 ( + ) ÷
8.4 + 7.9 － 6.4 18 × + 18 × 32 × 2.5 × 12.5
85.5 － 16.5 － 3.5 125 × 24 × 8 ×5 0.65 × 3.7 + 0.37 ×3.5
485 + 399 × 17 + 17 × 12.9 + 3 .7 + 6.3－2.9
三、解方程.
5X － 0.3 = 19.7 25%X + 45%X = 140 0.6 ：X = 2 ：8
8X + 7X = 30 4.5 ：X = 3 ：10 （ 1 － 30%） X = 35
1.5 ：9 = X ：6 X － 50%X = 12 4X － 30 = 110
12 ：X = 2 ：6 0.5X － 0.3 X = 10 5X + 25 = 100
四、计算下面各题.
763 － 852 ÷ 12 6.48 － 0.6 ÷ 1.5 +0.71 [ 1－ ( 0.5 + ) ] × 48
75.2 － 0.15 ÷ 0.5 × 0.9 ÷ [ 1 － ( +) ]
572 － 345 ÷ 23 ( 1 －) ÷ [ ( 0.75 －0.5 )÷] ×12
16.4 +12.6 ÷ 0.3 － ( 0.2 + ) × ÷ [1 ÷ ( + ) ]
÷×1 1－ ×－ ×[－(+)]
2 + 0.49 ÷0.7－0.45 12 .7 + 12.5 ÷ 5 × ( － ÷)
五、化简比
100:68 16.5:96.3 25.5:93 12.4:2/3
29.6:100/120 23.6:150 46:96 1.1:11
3.6:1.2 4.8:1/2 4.9:0.7 14:28.26 ：13 4123:4123 15:0.12
10:120 123:3 65:13 3:1 42:54 0.15:21
100:68 16.5:96.3 25.5:93 12.4:2
没办法把分数打出来.