a-b = 321
a:b = 4 rest 33
a = 4×b+33
a |___|___|___|___|+33
b |___|
4 segmente egale +33 - 1 segment egal = 3 segmente egale +33 = 321
321 - 33 = 288
288 : 3 = 96 ( un segmant )
a = 4×96 +33 = 384+33 = 417
b = 96
Verificare:
417-96 = 321
417:96 = 4 rest 33
a = 417
b = 96
