Răspuns :
a+b+c/3=30
b=2a
a+b=c
____________
c+c/3=30
2c/3=30 => 2c=3 x 30 => 2c=90 => c=45
a+b = 45 => a+2a=45 => 3a=45 => a=15
b = 2a => b= 2 x 15 => b=30
b=2a
a+b=c
____________
c+c/3=30
2c/3=30 => 2c=3 x 30 => 2c=90 => c=45
a+b = 45 => a+2a=45 => 3a=45 => a=15
b = 2a => b= 2 x 15 => b=30