Radius of the base of the cone \((r) = \frac{21}{2}\) meters Height \((h) = 14\) meters ∴ Slant height of the cone \((l) = \sqrt{\left(\frac{21}{2}\right)^2 + 14^2}\) meters \[ = \sqrt{\frac{441}{4} + 196} = \sqrt{\frac{441 + 784}{4}} = \sqrt{\frac{1225}{4}} = \frac{35}{2} \text{ meters} \] ∴ Curved surface area of the cone \(= πrl\) \[ = \frac{22}{7} × \frac{21}{2} × \frac{35}{2} \text{ square meters} = 577.5 \text{ square meters} \] ∴ At ₹1.50 per square meter, the cost to paint the curved surface of the cone \[ = 577.5 × 1.50 = ₹866.25 \quad \text{(Answer)} \]