1 直接写出得数。(每题1分,共20分)
$6.36 - 2.6 =$ $0.05 + 0.95 =$ $36.5 + 42.1 =$ $68 + 92.5 =$
$7.98 - 3.51 =$ $0 ÷ 4.61 =$ $4.68 - 3.29 =$ $2.3 × 20 =$
$0.8 × 0.5 =$ $19 - 14.7 =$ $56 + 32.5 =$ $8.3 + 1.7 =$
$29.8 + 37.6 =$ $8.4 + 6 =$ $31.8 + 46.9 =$ $0.25 × 4 × 1.2 =$
$0.45 ÷ 0.15 =$ $2.7 + 1.2 =$ $0.4 × 0.5 =$ $8.8 ÷ 2.2 =$

3.76 1 78.6 160.5
4.47 0 1.39 46
0.4 4.3 88.5 10
67.4 14.4 78.7 1.2
3 3.9 0.2 4

2 列竖式计算,带※的得数保留一位小数。(每题3分,共9分)
$2.6 × 1.08 =$ $4.8 ÷ 0.75 =$ ※$5.9 × 3.14 \approx$

竖式略
2.808 6.4 18.5

3 计算下列各题,能简算的要简算。(每题3分,共9分)
$3.8 + 4.29 + 2.1 + 4.2$ $4.37 × 5.1 - 0.49 × 3.6 + 4.73 × 4.9$ $(1275 + 1275) × 0.5$

14.39 43.7 1275

4 解方程。(每题4分,共12分)
$45 ÷ x = 0.9$ $2x ÷ 6 = 2.4$ $3(x - 1.8) = 24.6$

解:$x=50$ 解:$x=7.2$ 解:$x=10$