Question

A floor which measures 15 mx 8 m is to be laid
with tiles measuring 50 cm x 25 cm. Find the
number of tiles required. Further, if a carpet is laid
on the floor so that a space of 1m exists between
its edges and the edges of the floor, what fraction
of the floor is uncovered?
(ICSE)​

Answer 1

Answer:

Fraction uncovered = 420,000 / 1,200,000 = 7/20 or 0.35

Step-by-step explanation:

Area of floor = 1500 x 800 = 1 200 000 cm²

Area of tile = 50 x 25 = 1250 cm²

No. of tiles required = 1 200 000/1250 = 960 tiles

Space = 1m = 100cm; on both sides it will be 200 cm

Area of carpet = (1500 - 200) x (800 - 200) = 780,000 cm²

Uncovered area = 1 200 000 - 780,000 = 420,000 cm²

Fraction uncovered = 420,000 / 1,200,000 = 7/20 or 0.35