If a is 5 / 9 of B and B is 2 / 3 of C, how much less is a than C and how much is a (B plus C)?

If a is 5 / 9 of B and B is 2 / 3 of C, how much less is a than C and how much is a (B plus C)?

a=(5/9)b
a:b=5:9=10:18
b=(2/3)c
b:c=2:3=18:27
So, a: B: C = 10:18:27
a:c=10:27
A is 2 / 9 of (B + C)