Question
Find the base area $ A_B $ of a cone if slant height $l = 6\, \text{cm}$ and Curved Surface Area $CSA = 20\, \text{cm}$.
Answer
$1.1258\pi$
Explanation
STEP 1: find radius $ r $
To find radius $ r $ use formula:
$$ CSA = l \cdot r \cdot \pi $$After substituting $CSA = 20\, \text{cm}$ and $l = 6\, \text{cm}$ we have:
$$ 20\, \text{cm} = 6\, \text{cm} \cdot r \cdot \pi $$$$ r = \dfrac{ 20\, \text{cm} }{ 6\, \text{cm} \, \pi} $$$$ r = 1.061 $$STEP 2: find base area $ AB $
To find base area $ AB $ use formula:
$$ AB = r^2 \cdot \pi $$After substituting $r = 1.061\, \text{cm}^0$ we have:
$$ AB = 1.061 \cdot \pi $$ $$ AB = 1.1258 \cdot \pi $$This page was created using
Cone Calculator