The number 333 can be expressed as a fraction by placing it over 1. Therefore, in fraction form, it is 333/1.
To simplify a fraction, you look for the greatest common divisor (GCD) of the numerator and the denominator. In this case, the GCD of 333 and 1 is 1. Therefore, you divide both the numerator and the denominator by 1. This shows that 333/1 cannot be simplified further.
Thus, 333 written in its simplest fraction form is 333/1.