a. 0.1(6) = (16-1) sub 90 = 15 sub 90 = 1 sub 6
0.125 = 125 sub 1000 = 1 sub 8
0.25 = 25 sub 100 = 1 sub 4
a sub 6 = b sub 8 = c sub 4 = d sub 6 = k
a = 6 k
b = 8 k
c = 4 k
d = 6 k
6 k+8 k+4 k+6 k = 360
24 k = 360 = k = 15
a = 90 = b = 120 = c = 60 = d = 90