![](https://joidesresolution.org/wp-content/uploads/2017/06/3_3_tubes2_mini.jpg)
Enigma 6 resolved : Core on deck !
Seven rocks cores from the ocean floor…
among them a sediment core less dense than the others hard rocks cores …
How to find it using the balance only two times ?
A enigma that can be solved as follows (see attached) :