一、口算。
36 + 42 =
15 × 7 =
68 ÷ 4 =
82 × 3 =
120 - 64 =
37 × 10 =
310 × 3 =
515 ÷ 5 =
490 + 70 =
30 × 30 =
990 ÷ 3 =
3 × 220 =
360 ÷ 9 =
30 × 18 =
314 × 2 =
10 × 85 =
820 - 80 =
420 ÷ 3 =
6 × 103 =
848 ÷ 4 =
40 × 11 =
330 ÷ 6 =
15 × 40 =
30 × 23 =

一、78 105 17
246 56 370
930 103 560
900 330 660
40 540 628
850 740 140
618 212 440
55 600 690

二、用竖式计算，带 * 的要验算。
23 × 31
37 × 40
*58. × 15
70 × 26
61 × 34
*49. × 56

二、713 1480 870
1820 2074 2744