First, we need to calculate the length of the arc at the bottom right corner.
This arc is a quarter of a complete circle. The perimeter of a complete circle is computed as follows:

Then, the length of the arc is (the radius is 5):

Therefore, the perimeter of the figure is:
5 + 10 + 10 + 5 + 7.85 = 37.85 ≈ 38