Question

The area of the four walls of a room is \(88\) sq.m. Its height is \(4\) m and its floor space is square shaped. If it costs Rs.120 per sq.m. to tile its floor, the expenditure involved (in rupees) is

• A. \(3930\)
• B. \(3960\)
• C. \(3820\)
• D. \(3630\)

Hint:

For square rooms, use \(4 \times \text{side} \times \text{height}\) for four walls area.

Answer 1

The Correct Option is D

Concept: Area of four walls: \[ = \text{Perimeter of floor} \times \text{height} \] Since floor is square, let side be: \[ x \]

Step 1: Use area of four walls.
Perimeter of square: \[ 4x \] Given: \[ 4x \times 4=88 \] \[ 16x=88 \] \[ x=\frac{88}{16} \] \[ x=5.5 \]

Step 2: Find floor area.
\[ x^2=(5.5)^2 \] \[ =30.25 \] sq.m.

Step 3: Find tiling cost.
Cost per sq.m: \[ 120 \] So total cost: \[ 30.25\times120 \] \[ =3630 \] Thus, the expenditure involved is: \[ \boxed{3630} \]