Question

The area to be measured for painting distemper for an internal surface of a plastered 230 mm thick brick wall having dimension of 3000 mm length and 3200 mm height and having a glazed louvered ventilator of size 600 mm × 400 mm in the wall is
1. 9.60 sq.m
2. 9.36 sq.m
3. 9.84 sq.m
4. 9.12 sq.m

Answer 1

Correct Answer - Option 2 : 9.36 sq.m

Concept:

For a wall of given length ‘L’ and height ‘H’

Area of wall = L × H

Area of the wall to be painted = (Area of a wall) – (Area of ventilation)

Where an area of ventilation may include the area of doors and windows

For the window of length ‘l’ and height ‘h’

Area of ventilation = l × h

Calculation:

Given,

L = 3000 mm = 3 m, H = 3200 mm = 3.2 m

l = 600 mm = 0.6 m, h = 400 mm = 0.4 m

Area of wall = L × H = 3 × 3.2 = 9.6 m²

Area of ventilation = l × h = 0.6 × 0.4 = 0.24 m²

∴ Area of the wall to be painted = (Area of a wall) – (Area of ventilation)
∴ Area of the wall to be painted = (9.6) – (0.24) = 9.36 m²

Hence the area of the wall to be painted  = 9.36 sq.m