一、口算。
$80 - 60 =$
$56 + 3 =$
$37 - 5 + 20 =$
$6 + 57 =$
$77 - 60 =$
$45 + 15 - 13 =$
$24 + 34 =$
$68 - 36 =$
$57 - 49 + 12 =$
$16 + 44 =$
$7 + 67 =$
$52 - 8 - 22 =$
$5 + 38 =$
$46 - 9 =$
$70 + 14 - 16 =$
$98 - 75 =$
$8 + 25 =$
$78 - 23 - 37 =$
$44 + 46 =$
$82 - 17 =$
$17 + 50 + 23 =$
$39 - 5 =$
$33 - 20 =$
$80 + 7 - 40 =$
$64 - 9 =$
$42 + 53 =$
$95 - 32 + 17 =$
$72 + 16 =$
$60 - 35 =$
$39 + 46 - 33 =$

1.20
2.59
3.52
4.63
5.17
6.47
7.58
8.32
9.20
10.60
11.74
12.22
13.43
14.37
15.68
16.23
17.33
18.18
19.90
20.65
21.90
22.34
23.13
24.47
25.55
26.95
27.80
28.88
29.25
30.52

二、填一填。

第一行：58 67 76 85 94
第二行：47 36 25 14 3