Question 1062142
Here's a list of all possible outcomes, 3 face values and sum.
.
.
.

0	0	0	0
0	0	2	2
0	0	4	4
0	0	6	6
0	0	8	8
0	0	10	10
0	2	0	2
0	2	2	4
0	2	4	6
0	2	6	8
0	2	8	10
0	2	10	12
0	4	0	4
0	4	2	6
0	4	4	8
0	4	6	10
0	4	8	12
0	4	10	14
0	6	0	6
0	6	2	8
0	6	4	10
0	6	6	12
0	6	8	14
0	6	10	16
0	8	0	8
0	8	2	10
0	8	4	12
0	8	6	14
0	8	8	16
0	8	10	18
0	10	0	10
0	10	2	12
0	10	4	14
0	10	6	16
0	10	8	18
0	10	10	20
2	0	0	2
2	0	2	4
2	0	4	6
2	0	6	8
2	0	8	10
2	0	10	12
2	2	0	4
2	2	2	6
2	2	4	8
2	2	6	10
2	2	8	12
2	2	10	14
2	4	0	6
2	4	2	8
2	4	4	10
2	4	6	12
2	4	8	14
2	4	10	16
2	6	0	8
2	6	2	10
2	6	4	12
2	6	6	14
2	6	8	16
2	6	10	18
2	8	0	10
2	8	2	12
2	8	4	14
2	8	6	16
2	8	8	18
2	8	10	20
2	10	0	12
2	10	2	14
2	10	4	16
2	10	6	18
2	10	8	20
2	10	10	22
4	0	0	4
4	0	2	6
4	0	4	8
4	0	6	10
4	0	8	12
4	0	10	14
4	2	0	6
4	2	2	8
4	2	4	10
4	2	6	12
4	2	8	14
4	2	10	16
4	4	0	8
4	4	2	10
4	4	4	12
4	4	6	14
4	4	8	16
4	4	10	18
4	6	0	10
4	6	2	12
4	6	4	14
4	6	6	16
4	6	8	18
4	6	10	20
4	8	0	12
4	8	2	14
4	8	4	16
4	8	6	18
4	8	8	20
4	8	10	22
4	10	0	14
4	10	2	16
4	10	4	18
4	10	6	20
4	10	8	22
4	10	10	24
6	0	0	6
6	0	2	8
6	0	4	10
6	0	6	12
6	0	8	14
6	0	10	16
6	2	0	8
6	2	2	10
6	2	4	12
6	2	6	14
6	2	8	16
6	2	10	18
6	4	0	10
6	4	2	12
6	4	4	14
6	4	6	16
6	4	8	18
6	4	10	20
6	6	0	12
6	6	2	14
6	6	4	16
6	6	6	18
6	6	8	20
6	6	10	22
6	8	0	14
6	8	2	16
6	8	4	18
6	8	6	20
6	8	8	22
6	8	10	24
6	10	0	16
6	10	2	18
6	10	4	20
6	10	6	22
6	10	8	24
6	10	10	26
8	0	0	8
8	0	2	10
8	0	4	12
8	0	6	14
8	0	8	16
8	0	10	18
8	2	0	10
8	2	2	12
8	2	4	14
8	2	6	16
8	2	8	18
8	2	10	20
8	4	0	12
8	4	2	14
8	4	4	16
8	4	6	18
8	4	8	20
8	4	10	22
8	6	0	14
8	6	2	16
8	6	4	18
8	6	6	20
8	6	8	22
8	6	10	24
8	8	0	16
8	8	2	18
8	8	4	20
8	8	6	22
8	8	8	24
8	8	10	26
8	10	0	18
8	10	2	20
8	10	4	22
8	10	6	24
8	10	8	26
8	10	10	28
10	0	0	10
10	0	2	12
10	0	4	14
10	0	6	16
10	0	8	18
10	0	10	20
10	2	0	12
10	2	2	14
10	2	4	16
10	2	6	18
10	2	8	20
10	2	10	22
10	4	0	14
10	4	2	16
10	4	4	18
10	4	6	20
10	4	8	22
10	4	10	24
10	6	0	16
10	6	2	18
10	6	4	20
10	6	6	22
10	6	8	24
10	6	10	26
10	8	0	18
10	8	2	20
10	8	4	22
10	8	6	24
10	8	8	26
10	8	10	28
10	10	0	20
10	10	2	22
10	10	4	24
10	10	6	26
10	10	8	28
10	10	10	30
.
.
.
Look at all 216 possible outcomes, 35 of them have a sum greater than 20.

{{{P=35/216}}}