Question

The dimensions of a room are 9m$\times$8m$\times$6.5m. It has one door of dimensions 2 m$\times$1.5m and two windows each of dimensions 1.5m$\times$1m. Find the cost of whitewashing the walls at Rs6.40 per m${}^2$​.

• A. Rs. 2297.6
• B. Rs. 2207.2
• C. Rs. 2107.2
• D. Rs. 2007.2

Answer 1

The correct option is A

Rs. 2297.6

Total Surface Area = 2(lb+bh+hl) = 2(72 + 52 + 58.5) = 365m${}^2$​

Area that is to be white washed = 365 - (2$\times$ 1.5) - 2(1.5 $\times$1) = 359 m${}^2$​

Cost of White Washing = 359 $\times$ 6.4 = Rs.2297.6