for board with one suit x

x s s 11/50 * 38/49 * 37/48=.1304

s x s 39/50 * 11/49 * 38/48=.1386

s s x 39/50 * 38/49 * 11/48=.1386
I didn't check what you were actually doing, but I highly suspect these should all be the same. Prolly 'cause for the first one you used 38/49 and 37/48 when you were meant to use 39/49 and 38/48.