A trapezium plate having two parallel sides of length 15 cm and 9 cm. and distance between them is 6 cm. Copper plating is to be done on the plate at a rate of Rs.3 per square cm. What will be the total cost of copper plating on the upper side of the plate?

Rs.216

We know that,

 Area = \(\frac{1}{2}\) × (sum of lengths of parallel sides) × (distance between the parallel sides)

Area = \(\frac{1}{2}\) × (15 + 9) × 6 = 72 cm²

If the cost of copper plating = Rs. 3/cm²

Total cost = 72 × 3 = Rs. 216