Приемы устных вычислений вида 450+30, 620-200.
7 months ago 00:14:39 1
7 months ago 00:05:16 4
7 months ago 00:07:08 1
7 months ago 00:04:10 1
7 months ago 00:06:01 2
7 months ago 00:06:22 1
7 months ago 00:01:47 1
7 months ago 00:12:53 1
7 months ago 00:53:40 1
7 months ago 00:04:37 1
7 months ago 00:02:01 1
7 months ago 00:02:31 1
7 months ago 00:08:21 1
7 months ago 00:02:51 1
7 months ago 00:01:29 1
7 months ago 00:04:12 1
7 months ago 00:04:46 1
7 months ago 00:09:38 1
7 months ago 00:10:01 1
8 months ago 00:13:59 1
8 months ago 01:51:01 1
8 months ago 01:01:04 1
8 months ago 00:01:46 1
8 months ago 00:09:43 1
