$1 \frac{1}{3} \times 12=$

Step 1 ：Convert the mixed number $1 \frac{1}{3}$ to an improper fraction, which gives $\frac{4}{3}$.

Step 2 ：Multiply the fractions $\frac{4}{3} \times 12$ to get $\frac{4 \times 12}{3}$.

Step 3 ：Simplify the fraction $\frac{48}{3}$ to get $16$.

Step 4 ：\(\boxed{16}\) is the final answer.