To find the total floor area, \( n \), of all the offices, you would multiply the number of offices by the floor area of each office. Therefore, the correct equation is:
\[ 23 \times 305 = n \]
Calculating this gives:
\[ n = 23 \times 305 = 7,015 \text{ square feet} \]
So, the correct response is:
23×305=n, n=7,015 square feet