13 14/15=209/15 and 8 3/5=43/5.
209/15=n=43/5 implies 209/15=43/5=129/15 which is false. (Both fractions are shown as multiples of a fifteenth, 209 and 129, and 209≠129. The difference between the two fractions is 80/15=16/3=5 1/3.)
So perhaps the question should be: which integer lies between the two fractions?
13 14/15=14-1/15 and 8 3/5=9-2/5. 14-1/5≥n≥9-2/5. n≤14-1/5 implies n<14 and n≥9-2/5 implies n≥9.
Therefore n can have values 9, 10, 11, 12, 13 or 9≤n<14. The range of n is over 5 integers.
This is easy to see on a number line:
0---------8---(8 3/5)--9<----n---->13-----(13 14/15)-14----