Question

A room is 6 m long, 4.5 m wide and 5 m high. Find the cost of papering its walls with paper 1 m wide which is available at 40 paise per meter.

Answer 1

Given:

Length = 6 m, Breadth = 4.5 m, Height = 5 m.

Paper width = 1 m, Cost = 40 paise per metre.

Step-wise calculation:

1. Perimeter of room

= 2(Length + Breadth) 

= 2(6 + 4.5)

= 21 m

2. With paper 1 m wide, number of strips required

= `"Perimeter"/1` 

= 21 strips

3. Length of each strip = Height = 5 m.

4. Total length of paper required

= 21 × 5

= 105 m

5. Total cost

= 105 m × 40 paise/m 

= 4200 paise

= ₹ 42.00

The cost of papering the walls is ₹ 42.00.