Question

A black board of sides 5m 20cm and 3m 40cm is to be painted. Find the cost at the rate of rs 12 per square metre.

Answer 1

Let the sides be l and b

here l = 5 m 20 cm = 5.20 m
b = 3 m 40 cm = 3.40 m

area of black board = lxb
= 5.20 x 3.40 = 17.68 m^2

cost of painting = 17.68 x 12
= Rs 212.16