Răspuns :
A+B+C=750
A-x=17
B-x=19
C-x=21 Deci
17+x +19+x +21+x=750
3x + 57 =750
3x = 750- 57= 693 Deci x = 693/3 =231
Asadar A= 17+ 231= 248
B= 19 + 231 = 250
C= 21+ 231 = 252
750-{17+19+21=693. 693:3=231. Nr sunt 229;231 si 233...
229+17=246 231+19=250si 233+21=254