Path D-F-K Length and Net Area
The path length, in this case, is the plate width (10") less three EFFECTIVE HOLE DIAMETERS:
EFFECTIVE HOLE DIAMETER = bolt dia. + 1/16" for std hole + 1/16" damage allowance
Path Length = 10" - (3 hole diameters)*(7/8" + 1/8") = 7.00 inches
The net area equals the path length times the plate thickness:
Net Area for a single plate = (7.00")(.375") = 2.63 in2
Net Area for both plates = 2*2.63 in2 = 5.25 in2