A = 36/6 = 6
B = 50/5 = 10
C = 18/3 = 6
D = 29/6 = (24 + 5)/6 = 24/6 + 5/6 = 4 + 5/6
E = 34/3 = (33 + 1)/3 = 33/3 + 1/3 = 11 + 1/3
F = 43/6 = (42 + 1)/6 = 42/6 + 1/6 = 7 + 1/6
It's not clear what the unlock code is supposed to look like, but if it's simply
A - B - C - D - E - F
then the code would be
6 - 10 - 6 - 4 5/6 - 11 1/3 - 7 1/6