#### Question

Hameed has built a cubical water tank with lid for his house, with each other edge 1 .5 m long. He gets the outer surface of the tank excluding the base, covered with square tiles of side 25 cm. Find how much he would spend for the tiles, if the cost of tiles is Rs. 360 per dozen.

#### Solution

Given that

Hameed is giving 5 outer faces of the tank covered with tiles he would need to know the

surface area of the tank, to decide on the number of tiles required.

Edge of the cubic tank = `1.5m=150cm=a`

Area of each square tile = `("surface area of tank")/("area of each title")`

`=(5xx150xx150)/(25xx25)=180`

`("Cost of 1 dozen tiles i.e., cost of 12 tiles = Rs. 360")`

`("Therefore, cost of 12 balls tiles = Rs. 360")`

`∴"cost of one title" = (360)/(12)=rs.30`

`∴ The cost of 180 title= 180xxRs.30`

`=Rs.5.400`