What is the least number of square tiles required to pave the floor of a room 15 m 17 cm long and 9 m 2 cm broad ?

Answer: Option D

Required number of tiles are $$=\frac{\text{Area of floor}}{\text{Area of tiles}}$$
Sides of tiles is HCF (1517, 902) = 41
∴ Area of tiles = 41 × 41
∴ Number of tiles $$=\frac{1517\times 902}{41\times 41}=814$$