Provide your best answer for the following math problem. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The problem is: if [ x ] is the greatest integer less than or equal to x , what is the value of [ - 11.6 ] + [ 13.4 ] + [ 12.7 ] ?
13
10.3.