Question
Find the area $ A $ of a circle if diameter $d = 25.2\, \text{mm}$.
Answer
$158.76\pi\, \text{mm}^2$
Explanation
STEP 1: find radius $ r $
To find radius $ r $ use formula:
$$ d = 2 \cdot r $$After substituting $d = 25.2\, \text{mm}$ we have:
$$ 25.2\, \text{mm} = 2 \cdot r $$ $$ r = \dfrac{ 25.2\, \text{mm} }{ 2 } $$ $$ r = 12.6\, \text{mm} $$STEP 2: find area $ A $
To find area $ A $ use formula:
$$ A = r^2 \cdot \pi $$After substituting $r = 12.6\, \text{mm}$ we have:
$$ A = \left( 12.6\, \text{mm} \right)^{2} \cdot \pi $$ $$ A = 158.76\, \text{mm}^2 \cdot \pi $$This page was created using
Circle Calculator