1. The problem is to subtract two numbers: $93.1$ and $6 - 2.8$. 2. First, simplify the expression inside the subtraction: $6 - 2.8 = 3.2$. 3. Now rewrite the original expression: $93.1 - 3.2$. 4. Perform the subtraction: $93.1 - 3.2 = 89.9$. Final answer: $89.9$