Answer:
B. 45%
Step-by-step explanation:
The total number of seats in the auditorium = 400
Number of occupied seats = 220
Thus, the number of unoccupied seats = 400-220 = 180
So, the percentage of seats that were unoccupied will be:
![\begin{gathered} =(180)/(400)*100 \\ =(180)/(4)\% \\ =45\% \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/io4gg5q4gyzzgb8aztndfnsd6fl4x8oc1r.png)
The correct choice is B.