The cost of preparing the walls of a room 12 m long at the rate of Rs. 1.35 per square metre is Rs. 340.20 and the cost of matting the floor at 85 paise per square metre is Rs. 91.80. Find the height of the room.

Given,

Length of room = 12m

Let breadth of room = b m

Let height of room = h m

So, lateral surface area of room = 2(l+b)h m²

Area of floor = l×b m²

Cost of matting the floor = area of floor × rate of matting

= 91.80 = l×b ×.85

= b =

Cost of preparing wall = area of four walls ×rate of preparing

= 340.20 = 2(l+b)h ×

=