Correct option is C
Given:Length of room
=15 m 17 cm=1517 cm
Breadth of room
=9 m 2 cm=902 cm
Concept used:To find the least number of square tiles to cover the floor,
we use the largest square tile that divides both dimensions exactly.
This side length is the HCF of length and breadth.
HCF of 1517 and 902 using Euclidean algorithm:
1517÷902=1 remainder 615902÷615=1 remainder 287615÷287=2 remainder 41287÷41=7 remainder 0=>HCF=41 cm
Area CalculationsArea of floor
=1517×902=1367834 cm2
Area of one tile
=412=1681 cm2
Number of tiles
=16811367834=814
Crrect answer is (C)
814.