Question

A square room is 4 m high. The area of its floor is 144 sq. m. Find the cost painting its four walls inside at the rate of ₹ 2.50 per sq. m.

Answer 1

first given area = 144m²

so side = √area

= √144

=√12 × 12

= 12m

now lateral surface area of cuboid = 2 (l + b) ×h

= 2 (12 + 12) × 4

=2 ×24×4

=192m²

now, cost of painting = 2.50 × 192

=₹480