Question

the length of a room is 3 times its height and breadth is 3/2times its height the cost of whitewashing the wall @ Rupees 1.50 per square metre is rupees 16 find the dimensions of the room

Answer 1

Solution :-

There is a mistake in the question. I think the total cost of whitewashing the four walls of the room must be Rs. 216 instead of Rs. 16. 

Let the height of the room be x meters

Then, the length will be 3x meters and the breadth will be 3x/2 meters

Now, Total cost of whitewashing the four wall is Rs. 216 and the cost of whitewashing is Rs. 1.50 per square meter.

Therefore, the painted area = 216/1.5

= 144 sq m

So, the area of the four walls is 144 sq m

Lateral Surface Area of Cuboid = 2H(L + B)

⇒ 2x(3x + 3x/2)

⇒ 2x(6x + 3x)/2

⇒ 2x*(9x/2)

⇒ 18x²/2 = 144

⇒ 9x² = 144

⇒ x² = 144/9

⇒ x² = 16

⇒ x = √16

⇒ x = 4 m

Height is 4 m

So, length = 12 m and breadth = (4*3)/2 = 6 m

Answer.

Answer 2

Step-by-step explanation:

• Hope this will help you