Question 18
Jethro tiles a $10\text{ cm}\times15\text{ cm}$ floor with the pictured J-shaped tiles. Each tile consists of six $1\text{ cm}\times1\text{ cm}$ squares. Tiles may be turned, but may not be cut or overlap. What is the smallest uncovered area, in $\text{cm}^2$?
Interpretation: tiles follow the unit-square grid, as in the source construction.
Interpretation: tiles follow the unit-square grid, as in the source construction.