The radii o

Given: Radius of lower circular end = r = 12 cm

Radius of upper circular end = R = 18 cm

Height of frustum = h = 8 cm

Formula: Total surface area of frustum = πr² + πR² + π(R + r)l cm²

Where l = slant height

For slant height we have

∴ l = 10 cm

∴ total surface area of frustum = π × 12² + π × 18² + π × (18 + 12) × 10 cm²

= 3.14 × (144 + 324 + 300) cm²

= 3.14 × 768 cm²

= 2411.52 cm²

∴ total surface area of frustum = 2411.52 cm²