Question

A room is 7 m long and 5 m broad. It has door measuring 2m*1.5 m and two Windows, each measuring 1. 5* 1m. The cost of painting the walls at rs. 12. 50 per m^2 is rs. 825. Find the height of room

Answer 1

Let height of room be h m

Therefore,
Area of four walls = 2h(7+5)m2 = 24m2
Area of walls without doors and windows(as doors and windows cannot be painted) = 24h-(2x1.5 + 2x1.5x1)m2
= 24h-6m2

Therefore,

(24h-6) x12.50 = 825
or, 24h - 6 = 825/12.50 = 66
or, 24h = 72
or, h = 3

Answer: - Height of room is 3m.