From the given options, choose the correct one that will replace the question mark (?) in the following series.
1, 5, 3, 2, 10, 6, 4, 15, 9, 8, ?, 12
1
20
2
19
3
15
4
18
From the given options, choose the correct one that will replace the question mark (?) in the following series.
1, 5, 3, 2, 10, 6, 4, 15, 9, 8, ?, 12