Puzzle: numerical pattern recognition IF
7 - 3 = 10124
6 + 3 = 3279
5 – 2 = 763
11 + 2 = 92613

Then,
15 - 3 =? 

Any ideas ? I dont know how I am supposed to go about solving puzzles like this one ? is there any strategy ? any algorithm ?
 A: This is all I can come up with:
1:  Do the operation, the answer to that will be placed on the far right:
$
\begin{align}
7-3 &= 4 \\
6 + 3 &=9 \\
5-2 &= 3 \\
11 + 2 &= 13
\end{align}$
2:  Take the solution from above, multiply by the second digit in the original expression.  Place it to the left of the answer we got in 1.:
$
\begin{align}
4\cdot 3 &= 12 \\
9\cdot 3&=27 \\
3\cdot 2&= 6 \\ 
13 \cdot 2 &= 26
\end{align}$
So, we have
$
\begin{align}
124 \\
279 \\
63 \\ 
2613
\end{align}$
3:  If the original operation was addition, subtract, and vice versa.  Stick this number to the left of the concatenated solutions to 1 and 2:
$
\begin{align}
7+3 &= 10 \\
6 - 3 &=3 \\
5+2 &= 7 \\
11 - 2 &= 9
\end{align}$
Thus, we have
$
\begin{align}
10124 \\
3279 \\
763 \\ 
92613
\end{align}$
A: It would be $15-3 = 183612$. Answers are $(\text{opposite operation})(\text{answer} \times\text{second operand})(\text{actual computation})$
A: WARNING: full answer
Note that 7 + 3 = 10, (7-3)*3 = 12, 7 - 3 = 4
Concatenate to get 10124
For the next one, 6 - 3 = 3, (6+3)*3 = 27, and 6+3 = 9
Concatenate to get 3279
Do a similar process for the other two.  Its a weird pattern, but its there.  And there isn't a general way to solve stuff like that, its just pattern recognition.
A: 15-3 =?
(15+3)((15-3)*3)(15-3)
183612 
