Răspuns :
a+b+c=60000
a+b=40000
c=a-15000 => a=c+15000
40000+c=60000
c=60000-40000
c=20000
a=20000+15000
a=35000
35000+b=40000
b=40000-35000
b=5000
35000+5000+20000=60000
a+b+c=60000
a+b=40000
c=a-15000 => a=c+15000
40000+c=60000
c=60000-40000
c=20000
a=20000+15000
a=35000
35000+b=40000
b=40000-35000
b=5000
35000+5000+20000=60000