Question

a floor measuring 7m by 2.8 m is to be covered with tiles measuring 35cm square. how many tiles will be needed

Answer 1

Solution :

i ) Dimensions of the floor :

Length ( l ) = 7 m

Breadth ( b ) = 2.8 m

Area of the floor ( A ) = lb

A = 7 m × 2.8 m

A = 700cm × 280 cm -----( 1 )

ii ) side of each square tile(a)=35cm

Area of the each tile = a² cm²

iii ) Let the number of tiles

required = n

n = ( lb )/a²

n = ( 700 × 280 )/( 35 )²

n = ( 700×280 )/( 35×35 )

n = 160

Therefore ,

Number of square tiles required

= n = 160

••••

Answer 2

length of the floor = 7m
7 × 100 = 700cm

breadth of the floor = 2.8m
2.8 × 100 = 280cm

Now,
Area of the floor = length×breadth unit sq.

Area of the floor = 700 × 280 cm²

Area of the floor = 19600 cm²

Now,
area of a tile is 35 cm²,

Number of tiles required to cover the floor of 19600 cm² are -

$\frac{19600}{35} = 560$

Hence, 560 numbers of tiles measuring area 35cm² will cover the floor of area 19600 cm².