Given that a: B: C = 2:3:4 and 3a + 5b-4c = 15, find the values of a, B and C

Given that a: B: C = 2:3:4 and 3a + 5b-4c = 15, find the values of a, B and C

a:b:c=2:3:4
Then C = 2A
b=3a/2
Substituting 3A + 5b-4c = 15
3a+15a/2-8a=15
5a/2=15
therefore
a=6
b=3a/2=9
c=2a=12