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A circular board has radius 3 m. Painting costs ₹50 per m². If 15% is unpainted, what is the total cost?

1. ₹ 1185
2. ₹ 1202
3. ₹ 1275
4. ₹ 1350

Correct answer: ₹ 1202

Solution

Area of the board = \(\pi \times 3^2 = 9\pi\) m². Painted area = 85% of \(9\pi\) = \(7.65\pi\) m². At ₹50 per m², cost = \(7.65\pi \times 50 \approx ₹1202\).

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