Notez ,,clasele" cu: I ; II ; III ; IV
stiim ca :
I + II + III + IV=986 (elevi)
I+II+III = 715 ... => IV = 986-715 = 271 elevi ;
II+III = 498
III+IV = 525 ... => III = 525-271 = 254 elevi ;
... => II = 498-254 = 244 elevi ;
... => I = 986-(271+244+254) = 217 elevi ;