First you need one full inch, which is 64/64. Out of that you can have 12 layers or 12x5/64=60/64 which leaves you with an extra 4/64 to use in the rest. Now your quarter inch, or 16/64, can create 3 layers, or 3x5/64=15/64 which leaves you with 1/64. That combined with the 4/64 in the part before gives you one more layer. Therefore, hockey ice has 16 (12+3+1) layers.
