+	1	2	3	4	5	6
1	2	3	4	5	6	7
2	3	4	5	6	7	8
3	4	5	6	7	8	9
4	5	6	7	8	9	10
5	6	7	8	9	10	11
6	7	8	9	10	11	12

P(a sum of 7) = \(\frac{6}{36}\) and P(a sum of 4) = \(\frac{3}{36}\)
P(a sum of 4) = \(\frac{3}{36}\)
P(a sum of 7 and a sum of 4) = \(\frac{6}{36} \times \frac{3}{36}\) = \(\frac{1}{72}\)