I think you can divide that number by either 1 or 0
Find total surface area (18*12)*2+ (18*8)*2+ (12*8)*2= 192 +288 432+288+192= 912
then subtract surface area of doors
(3*7)2=42 then subtract windows 3*5(3)=45 then subtract the floor 18*12=216
912-42-45-216= 609 sq ft he should only need 2 and a small portion of a third to paint your room i believe what his math must have been was 18*12*8=1728 then subtract -42-45-216 for the floor windows and doors to get 1425 and even then he underestimates with his inaccurate figures
so first 609 sq ft he should only need 2 and a small portion of a third to paint your room and 2 get a new painter bcus this guy cant math hope i helped if so give brainliest answer-J (:
I need a better picture then I could answer
