Mike,

(Wet weight times 75% dry matter) divided by 85% dry matter

(31.4 x 0.75) / 0.85 = 27.7 g at 15% moisture

In terms of "pencil shrink", each percentage point of moisture removed from grain reduces its weight by 1.18%. So, ten points removed (25 - 15) = 11.8% reduction in weight or 3.7 g (31.4 x 0.118). Original 31.4 g minus 3.7 g = 27.7 g at 15% moisture.

Remember that this mathematical exercise has no relationship to test weight. It only applies to kernel weight.