a+b+c=8.2
a+b+2{c}=7.9
a+b+2{b}=9.3
=> [c]-{c}=0.3 so [c]=1 {c}=0.7 then c=1.7
[b]-{b}=-1.1 so [b]=-1 {b}=0.1 then b=-1.1
so a=7.6 b=-1.1 c=1.7
a+b+2{c}=7.9
a+b+2{b}=9.3
=> [c]-{c}=0.3 so [c]=1 {c}=0.7 then c=1.7
[b]-{b}=-1.1 so [b]=-1 {b}=0.1 then b=-1.1
so a=7.6 b=-1.1 c=1.7