Notam cu a suma pe care o avea Andrei
[(3xa-100)x2-82]:2-60=1980
[(3xa-100)x2-82]:2=1980+60
[(3xa-100)x2-82]:2=2040
(3xa-100)x2-82=2040x2
(3xa-100)x2-82=4080
(3xa-100)x2=4080+82
(3xa-100)x2=4162
3xa-100=4162:2
3xa-100=2081
3xa=2081+100
3xa=2181
a=2181:3
a=727 lei a avut Andrei initial