How many times is 9 preceded by either 6 or 1 and followed by either 5 or 8 in the following series?
8 9 5 1 7 6 9 8 2 1 9 8 4 3 5 9 1 3 6 9 51
1
2
2
3
3
4
4
How many times is 9 preceded by either 6 or 1 and followed by either 5 or 8 in the following series?
8 9 5 1 7 6 9 8 2 1 9 8 4 3 5 9 1 3 6 9 5