Given: Length = 16 meters Breadth = 12 meters Height = 15 meters Concept: Length of the largest rod that can be put in a room is equal to the length of the diagonal of that room. Formula used: Diagonal of a cuboid =√(l2+b2+h2) Where l, b, and h are respectively the length, breadth, and height of a room Calculation: Length of longest rod =√(162+122+152) ⇒ Length of longest rod =√(256+144+225)=√625 ∴ Length of longest rod = 25 cm