一、口算。
$60 - 15 =$
$8.1 ÷ 9 =$
$0.7 × 3 =$
$6 ÷ 5 =$
$7.2 + 4.3 =$
$0.02 ÷ 100 =$
$43.1 × 10 =$
$20 × 26 =$
$3.6 - 1.9 =$
$52 ÷ 13 =$
$2.86 - 1.82 =$
$2.5 × 50 =$
$4.06 × 5 =$
$9.6 ÷ 24 =$
$9.17 + 1.9 =$
$480 + 40 =$
$14 × 600 =$
$140 ÷ 14 =$
$2.6 × 7 =$
$0.48 ÷ 8 =$
$1.1 - 0.26 =$
$0.45 ÷ 15 =$
$0.13 × 4 =$
$2.27 + 1.91 =$
$7.2 ÷ 12 =$
$2.1 ÷ 5 =$
$0.05 × 40 =$
$0.125 × 8 =$
$11.1 × 30 =$
$40 ÷ 25 =$

1.45
2.0.9
3.2.1
4.1.2
5.11.5
6.0.0002
7.431
8.520
9.1.7
10.4
11.1.04
12.125
13.20.3
14.0.4
15.11.07
16.520
17.8400
18.10
19.18.2
20.0.06
21.0.84
22.0.03
23.0.52
24.4.18
25.0.6
26.0.42
27.2
28.1
29.333
30.1.6

二、猜灯谜。

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