Question 1: The answer is 54
Workings:
1 + 3 = 4
The formula used to achieve this is:
a + b = ab + a
Now let's verify
1 + 3 = 1×3 +1 = 4
2 + 4 = 2×4 + 2 = 10
3 + 5 = 3×5 + 3 = 18
Then
6 + 8 = 6×8 + 6 = 54

Question 2: What is the sum of the particular post in the given section is 5