0.75
The letter is L and the number is 12.
The number that completes the sequence would be 11. Imagine the sequence as two sequences of every other number starting with the first 2 and the first 6. You would have 2 3 6 and 6 8 12 2 3 6 is adding odd numbers starting with one. 6 8 12 is adding even numbers starting with two. The next number belongs to 2 3 6 so you would add 5 to get 11.
9
12/11 = 11/11
11
11
The sequence appears to alternate between adding and subtracting numbers. The pattern seems to be +11, -7, +5, -2, +6. Following this pattern, the next number in the sequence would be +3 from the previous number, which would be 21.
0.75
The letter is L and the number is 12.
The number that completes the sequence would be 11. Imagine the sequence as two sequences of every other number starting with the first 2 and the first 6. You would have 2 3 6 and 6 8 12 2 3 6 is adding odd numbers starting with one. 6 8 12 is adding even numbers starting with two. The next number belongs to 2 3 6 so you would add 5 to get 11.
eight
Pattern: +7,-4,+8,-3,+9,-2... Pattern continuation: +10,-1,+11,*0,+12,+1 17+10=27
9
the number between 11 and 12 is obvious. it is 11 and a half
15, since 15*2 = 9*2 + 12*2
33