Question

A rectangular hall is 16m long and 12m wide. How many marble slabs of size 25cm×15cm are needed to cover the floor of the hall

Answer 1

First we have to find the area of the hall
Area of the hall =l×b
=16×12
=192m^2
Area of the marble slab =25×15
=375cm^2
{1 m^2 =10,000 cm^2}
(Convert m^2 into cm^2)
192m^2=19,20,000 cm^2
Therefore, how many slabs required=1920000÷375
=5120.
Thus, 5120 tiles are needed to cover the floor.
Hence,proved.

Answer 2

First we have to find the area of the hall 
Area of the hall =l×b
=16×12
=192m^2
Area of the marble slab =25×15
=375cm^2
{1 m^2 =10,000 cm^2}
(Convert m^2 into cm^2)
192m^2=19,20,000 cm^2
Therefore, how many slabs required=1920000÷375
=5120. 
Thus, 5120 tiles are needed to cover the floor.
Hence,proved.