Risk statistics

From Carls wiki

Attacking and defending

The below table describes how many attackers are needed to defeat a given number of defenders with a given degree of certainty.

(The algorithm makes the assumption that the defender always defends with the maximum number of dice available: two, unless there is only one defending army left.)

def:s	10%	25%	50%	75%	80%	90%	95%	99%
1	1	1	2	2	3	3	4	5
2	1	2	3	4	5	6	7	9
3	2	3	4	5	6	7	9	11
4	3	3	5	6	7	9	10	14
5	3	4	5	8	8	10	12	17
6	3	4	6	9	9	11	13	18
7	4	5	7	10	11	13	15	19
8	4	6	8	11	12	14	16	21
9	5	6	9	12	13	15	18	22
10	5	7	10	13	14	16	19	22
11	6	8	10	14	14	18	20	25
12	6	8	12	15	15	19	21	25
13	7	9	12	16	17	20	22	26
14	8	10	13	17	18	21	23	28
15	8	11	14	18	19	22	24	29
16	9	11	15	19	20	23	27	31
17	9	12	16	20	21	24	27	32
18	10	13	16	21	22	25	29	34
19	11	14	18	22	23	27	29	34
20	12	14	18	23	24	28	31	35
21	11	15	19	24	25	29	30	37
22	12	16	20	25	26	30	33	39
23	13	16	21	25	27	31	33	39
24	15	18	22	27	28	31	35	40
25	14	18	22	28	29	33	36	42
26	15	19	24	29	30	34	37	44
27	16	20	24	30	31	34	38	43
28	17	21	25	30	31	36	38	43
29	17	21	26	32	32	37	41	46
30	18	22	27	32	35	38	41	49