Oh, I SEE what da pattern is! =D
You see, like in this problem:
2 + 5 = 12
They did 5 times 2 = 10, plus da 2 in da problem = 12.
Same with 3 + 6 = 21, 6 times 3 = 18, 18 plus da 3 given in da problem = 21.
Just like 1 + 4 = 5, 4 times 1 = 4, plus da 1 in da problem = 5.
SO,
with that strategy, 8 +11 = 96, because 8 times 11 = 88, plus da 8 given in da problem = 96.
I hope I helped! =D