First of all i dont agree that 6 5/12 is the answer

First is you find their LCD which is 12 then that 12 you will devide it to the both denominator then multiply to the numerator: and also if there is a mixed number turn it to improper.

11/12

12 ÷ 12 = 1

1 × 11 = 11

= 11/12

14/3

3 ÷ 12 = 4

4 × 14 = 56

= 56/12

4/6

6 ÷ 12 = 2

2 × 4 = 8

= 8/12

then add them together

11/12 + 56/12 + 8/12 = 75/12

then turn it to the lowest term

FINAL ANSWER : 6 3/12 or 6 1/4

「hope it helps po」