Question

A room is 15 metres long, 4 metres broad and 3 metres high. Find the cost of whitewashing its four walls at ₹0.5 per $m^2$.

• A. ₹60
• B. ₹57
• C. ₹55
• D. ₹52

Answer 1

The correct option is B ₹57

Length of the room = 15 m
Breadth of the room = 4 m
Height of the room = 3 m

Area of 4 walls $=2(l\times h)+2(b\times h)$
$=2(15\times 3)+2(4\times 3)$
$=90+24$
$=114m^2$
Hence, the cost of painting at the rate of ₹0.5 per $m^2$
$=\frac{1}{2}\times 114=₹57$