In the initial share by Akosha there is an amazing range of answers, from 16 to 56… so the 95%, while too exact (97.3% of all statistics are wrong!) may be in the ballpark.

My take: 

First, discern between visible balls, and balls making up that pile.

VIsible: 16, that's rather easy.

Full pile: we have a 4x4 bottom layer, then 3x3, 2x2, 1x1.

16 + 9 + 4 + 1 = 30 in my book. 

Anyone disagrees?

Originally shared by Tapzo

Can you count the number of balls?