# Math Help - Perimeter of oval

1. ## Perimeter of oval

Is there a way to calculate the perimeter of an oval with min. diameter 9 cm, and max. diameter 20 cm?

2. Originally Posted by DarkLightA
Is there a way to calculate the perimeter of an oval with min. diameter 9 cm, and max. diameter 20 cm?
Hi DarkLightA,

The approximate circumference of an ellipse is given by the formula:

$C=2 \pi \sqrt{\frac{1}{2}(a^2+b^2})$

where

a = half of the width diameter (referred to as semimajor axis)
b = half of the length diameter (referred to as semiminor axis)

Found here!

3. Thanks! That's awesome!