Final answer:
The area of the verandah is 140 m², and the cost to cement the verandah at ₹10 per square metre is ₹1,400.
Step-by-step explanation:
To find the area of the verandah and the cost of cementing it, we first need to calculate the overall dimensions of the room including the verandah. Since the verandah is 2.5 m wide all around, we add this width twice to the length and to the width of the room.
The new length is 14.5 m + 5 m (2.5 m on each side) = 19.5 m.
The new width is 8.5 m + 5 m (2.5 m on each side) = 13.5 m.
Now we calculate the area of the larger room including the verandah, which is 19.5 m * 13.5 m = 263.25 m². To find the area of the verandah alone, we subtract the area of the room from this result. The area of the room is 14.5 m * 8.5 m = 123.25 m².
So, the area of the verandah is 263.25 m² - 123.25 m² = 140 m².
The cost of cementing the verandah at ₹10 per square metre is 140 m² * ₹10/m² = ₹1,400.