**Guide :Middle School **

# Find the area of the four walls of a cubical room whose side measures 5m. Find the cost of white washing the room at the rate of `23 per square metre.

Find the area of the four walls of a cubical room whose side measures 5m. Find the cost of white washing the room at the rate of `23 per square metre.**We know that one wall side is 5m.To find the area of one wall, we do 5²=25m²We know there is 4 walls. So we have to find total area of all four walls.Which is 25×4=100m²To find the total cost of white washing the room, we have to do:100(total area)×23(cost per m²)=$2300So the total cost of the area is $2300**...