Question

A bucket of height $16cm$ made up of metal sheet is in the form of frustum of a right circular cone with radii of its lower and upper ends as $3cm$ and $15cm$ respectively. What is the slant height of the bucket?

• A. $15cm$
• B. $20cm$
• C. $5cm$
• D. $12cm$

Answer 1

Answer: (B)

$20cm$

Slant height = $\sqrt{{(R-r)}^2+h^2}=\sqrt{{(15-3)}^2+{16}^2}=\sqrt{144+256}$

= $\sqrt{400}=20cm$