Question

2. Arun has built a cubical water tank with lid and each outer
edge is 2.5 m long. The outer surface of the tank excluding
the base is covered with square tiles of side 25 cm long.
Find the number of tiles required.​

Answer 1

The surface area of the cubical tank = 6(a)^26(a)

2

, where 'a' is the edge of the cubical tank.

Since, the tank is covered with square tiles but excluding the base.

So, Surface area of cubical tank to be covered with tiles = 5(a)^25(a)

2

,

where 'a' is the edge of the cubical tank.

So, Surface area of tank = 5(2.5 m)(2.5 m)5(2.5m)(2.5m)

As 1 m = 100 cm

Surface area of tank = 5 \times 2.5 \times 100 \times 2.5 \times 1005×2.5×100×2.5×100

= 312500 cm^2cm

2

As, Area of square tile = (side)^2(side)

2

= (25 cm)^2(25cm)

2

= 625 cm^2cm

2

So, Number of tiles = Surface area of cubical tank \div÷ Area of 1 tile

= 312500 \div 625312500÷625

= 500