Question

find the volume of a frustum of base raddi 7cm and 3.5cm and height 2cm

Answer 1

R=7cm r=3.5cm Ht=2cm Volume =πh/3(R²+r²+R×r) =22×2/7×3(7²+3.5²+7×3.5) =44/21(49+12.25+24.5) =44/21(85.75) =179.67 cm³

Answer 2

Here given R₁ = 7 cm ,R₂ = 3.5 cm and height = 2 cm.

To find = Volume of a frustum of a cone.

Volume of frustum of a cone = πh/3 ( R₁² + R₂² + R₁ × R₂ )
                                          = 22/7 × 2/3 ( 7² + 3.5² + 7 × 3.5 )
                                          = 44/21 ( 49 + 12.25 + 24.5 )
                                          = 44/21 × 85.75
                                          = 3773/21
                                          = 179.67 cm³ approx.