13/16 because 4/16 and 9/16 have the same denominator which is 16 so you wont need to change anything and so you leave the deniminator alone and do 9+4 (which is the numerators of both fractions) and 9+4=13 so the answer is 13/16 and that can't be simplified because 13 can't be evenly divided by anything even though 16 can