If anyone has access to Advanced Concepts of GD&T 2nd edition by Alex K., I need clarification/help regarding figure 13-7, page 13-6 Chapter 13 Datum Systems Tolerance Stacks.

Specifically when calculating Max Distance X (A) and Min Distance X (A), I follow the calculation for Max Distance X (A); the basic dimension 15 less 1/2 of the hole MMC - tolerance of position (10.4 -0.2)/2 = 5.1; 15.0 - 5.1 = 9.9

However; calculating the Min Distance X (A) not so clear, rather foggy.

I get the 15 basic dimension, yet what is the rational for inclusion of the other numbers -10.6 and the +5.1???

The same can be said for calculating Max Distance X (B) & Min Distance X (B).

Any help navigating this key concept will be appreciated!!

Regards,

Marty