Answer:
-13.11
Explanation:
Remember: Please Excuse My Dear Aunt Sally (PEMDAS)
You use the parentheses first, so it is 18.03-3*(20.76)÷2
So then, you see there are no exponents, so you multiply and divide from left to right. So, 18.03-62.28÷2. Then you divide: 18.03-31.14
Then, you subtract from left to right, which gives you: -13.11