2. What is the value of the expression $18.15 \div-5 \frac{1}{2}$ in decimal form? Enter the correct answer in the box. Round to the nearest tenths place.

Step 1 ：Convert the mixed number $-5 \frac{1}{2}$ to an improper fraction, which is $-5.5$

Step 2 ：Perform the division operation $18.15 \div -5.5$ to get $-3.3$

Step 3 ：Round the result to the nearest tenths place, which is $-3.3$

Step 4 ：\(\boxed{-3.3}\)