a; b; c numerele
a - b = 177
a : b = 7 rest 21
a = 7×b + 21
c : b = 4 rest 17
c = 4×b+17
a |___|___|___|___|___|___|___|+21
b |___|
c |___|___|___|___|+17
7 segmente egale +21 - 1 segment egal = 6 segmente egale +21 = 177
177 - 21 = 156
156 : 6 = 26 ( un segment egal)
a = 7×26+21 = 182+21 = 203
b = 26
c = 4×26 + 17 = 104 + 17 = 121
Verificare:
203 - 26 = 177
203 + 26 + 121 = 350 (suma numerelor)