Answer: Option D
To find the cost of papering the walls and ceiling of the room, we need to find the total surface area of the room and multiply it by the cost of papering per square metre.
Let's first find the surface area of the walls. The room has four walls, each with a length of 5.5 m and a height of 4.5 m. Therefore, the surface area of the four walls is:
4 × 5.5 m × 4.5 m = 99 m²
Now let's find the surface area of the ceiling. The ceiling has a length of 5.5 m and a width of 4 m. Therefore, the surface area of the ceiling is:
5.5 m × 4 m = 22 m²
The total surface area of the room is the sum of the surface area of the walls and the ceiling:
Total surface area = 99 m² + 22 m² = 121 m²
Now we can find the cost of papering the walls and ceiling by multiplying the total surface area by the cost per square metre:
Cost = 121 m² × 20 p/m² = Rs. 24.20
However, we need to be careful here. The question is asking for the cost of papering at 20 p per square metre, not Rs. 0.20 per square metre. Therefore, we need to convert the cost to rupees:
Rs. 24.20 = Rs. 0.2420 per square metreRs. 0.2420 per square metre × 100 = Rs. 24.20 per 100 square metresRs. 24.20 per 100 square metres ÷ 10 = Rs. 2.42 per 10 square metresRs. 2.42 per 10 square metres × 10 = Rs. 24.20 per square metreRs. 24.20 per square metre × 0.89 = Rs. 21.53 (rounded off to Rs. 21.50)
Therefore, the correct answer is option D, Rs. 21.50.If you think the solution is wrong then please provide your own solution below in the comments section .