i feel like it’s either answer 2 or 4. i just don’t understand the -9 part

Answer:
n < 27
Step-by-step explanation:
let the number be n
[tex] \frac{1}{3} n - 3 < 6 \\ add \: 3 \: to \: both \: sides \\ \frac{1}{3}n - 3 + 3 < 6 + 3 \\ \frac{1}{3} n < \\ 9 \\ multiply \: both \: sides \: by \: 3 \\ \frac{1}{3} n \times 3< 9 \times 3 \\ n < 27[/tex]