How many square slabs each with side 90cm are needed to cover a floor of area 81sqm.
Given:
Side = 90 cm
Area of square lab = 90 × 90
= 8100 sq.cm
Area of slab = 81sq.m = 81 × 10000 = 810000 sq.cm
Number of slabs = 810000 / 8100
= 100