Find the perimeter of the ellipse with major-axis = 10 and minor-axis = 8.

major axis, $2a = 10$

$a = 5$
 

minor axis, $2b = 8$

$b = 4$
 

Perimeter of Ellipse (Approximate Formula)
$P = 2\pi \sqrt{\dfrac{a^2 + b^2}{2}} = 2\pi \sqrt{\dfrac{5^2 + 4^2}{2}}$

$P = 28.448$