We just need to find the multiples of 9 that are greater than 20.
9*1 = 9
9*2 = 18
9*3 = 27
9*4 = 36
9*5 = 45
We can use 27,36, 45, .....
Your final answer should be any multiple of nine greater than 20. I recommend using 27, 36, and 45. Hope this helps!