2
Explanation:
This is one of the easy number series riddles in which you just need to replace the alphabets from A to Z with 1 to 26.
i.e
A = 1
B = 2
.......
.......
.......
Z = 26
So considering 1st part of equation
D = 4 , W=23 and sum = 27
In a similar fashion.
U=21, L=12 and sum = 33.
In last part
G = 7 , O = 15 and sum = 22
Therefore answer is 2.