You need to change 2/9 and 1/6 so they have common denominators. 2/9 becomes 9/18 and 1/6 becomes 3/18. When you divide fractions, you use "keep, change, flip". You keep 2/9, change division to multiplication, and flip 1/6 to 6/1. Then you multiply across - 2 x 6 and 9 x 1. You end up with 12 over 9, which can be left as 12/9 or turned into either 1 and 3/9 or 1 and 1/3.
