Subtract Three Units from 73: Basic Arithmetic Operation

To solve this simple subtraction problem, let's follow the steps:
Step 1: Identify the numbers involved, which are $73$ and $3$.
Step 2: Apply the operation of subtraction to these numbers. The problem asks us to subtract $3$ from $73$, resulting in the mathematical operation $73 - 3$.
Step 3: Calculate the result of the subtraction: $73 - 3 = 70$.

Therefore, the result of subtracting three units from the number 73 is $70$.