1. 直接写出得数。
0.8 + 2.6 =
4.4 + 4.6 =
7.58 + 0.52 =
4.4 ÷ 11 × 10 =
9.6 - 0.8 =
2.9 - 1.8 =
0.3 ÷ 4 =
0.84 ÷ 4 × 3 =
4.3 × 10 =
0.8 × 9 =
7.2 × 2 =
0.38 ÷ 19 × 100 =
7.8 ÷ 6 =
2.03 × 4 =
0.3 × 7 =
5.2 ÷ 100 ÷ 10 =
2.6 ÷ 10 =
1.68 ÷ 4 =
4.3 × 2 =
9.1 ÷ 7 ÷ 13 =
3.6 × 2 =
11.2 - 3.6 =
9.8 ÷ 49 =
7.02 × 5 ÷ 10 =
0.2 × 60 =
0.13 × 7 =
0.72 ÷ 24 =
2.75 ÷ () = 0.0275
4.8 ÷ 48 =
20 ÷ 50 =
8.2 × 100 =
4.25 ÷ 5 - 0.3 =

1. 3.4 9 8.1 4
8.8 1.1 0.075 0.63
43 7.2 14.4 2
1.3 8.12 2.1 0.0052
0.26 0.42 8.6 0.1
7.2 7.6 0.2 3.51
12 0.91 0.03 100
0.1 0.4 820 0.55

2. 计算下面各题。
$800 - 560 ÷ 8 × 9$
$750 ÷ 15 + 70 × 12$
$49 × (32 - 17) ÷ 21$
$(92 - 45) × (650 ÷ 50)$
$(646 ÷ 38 + 27) × 53$
$675 ÷ [15 × (36 ÷ 12)]$

2. 170 890 35
611 2332 15

一根彩带，对折3次后沿折痕剪开，每一小段长2.13米。这根彩带原来长多少米？

2.13×8=17.04(米)