Maths Puzzle - 19

Guruji gave me this puzzle.

Try to solve this puzzle. She said only 1 Out of 100 Has been able to solve this. If you’re able to solve it you’re one of those … And your IQ is also above 150. (I don't think this is true. It is far too simple for that.)

IF

7 - 3 = 10124

6 + 3 = 3279

5 – 2 = 763

11 + 2 = 92613

Then,

15 - 3 = ?