A number x divided by 3 is at most 5.

"At most" refers to less than or equal to (≤).

This is because "at most" means no more than, must be less than, and can be equal to.

As an inequality, this would be written as x / 3 ≤ 5.

This means that x divided by 3 is less than or equal to (at most) 5.