[ 333 - ( 33X3 + 3 )] : 3 =
( 333 - 102 ) ; 3 = 231 : 3 = 77
I + II + III + IV = 77
III + IV = 44
I + II + 44 = 77
I + II = 77 = 44
I + II = 33
II /....../......./
I /....../
33 : 3 = 11 ( CLASA I)
11 X 2 = 22 ( CLASA II )
III /......./ + 5
IV /......../......../
44 - 5 = 39
39 : 3 = 13
III = 1 X 13 + 5
III = 18 ELEVI
IV = 13 X2 = 26 ELEVI
verificam
11 + 22 + 18 + 26 = 77 elevi