a : 6 = 7 rest 0
a = 7 × 6 + 0
a = 42 + 0
a = 42
b : 6 = 7 rest 1
b = 7 × 6 + 1
b = 42 + 1
b = 43
c : 6 = 7 rest 2
c = 7 × 6 + 2
c = 42 + 2
c = 43
d : 6 = 7 rest 3
d = 7 × 6 + 3
d = 42 + 3
d = 45
e : 6 = 7 rest 4
e = 7 × 6 + 4
e = 42 + 4
e = 46
f : 6 = 7 rest 5
f = 7 × 6 + 5
f = 42 + 5
f = 47