Australian AMC 2013 - Senior Question 14

Question 14

A square of perimeter 20 cm is inscribed in a square of perimeter 28 cm. What is the greatest distance between a vertex of the inner square and a vertex of the outer square, in centimetres?

Question illustration

$\sqrt{58}$
$\frac{7\sqrt5}{2}$
8
$\sqrt{65}$
$5\sqrt3$