Răspuns :
Ma = ( a + a+ 1 + a + 2) : 3 = 186
3×a + 3 = 186 × 3
3×a + 3 = 558
3×a = 558-3
3×a = 555
a = 555 : 3
a = 185
a+1 = 186
a+2 = 187
verificare:
185 + 186 + 187 = 558
558 : 3 = 186
3×a + 3 = 186 × 3
3×a + 3 = 558
3×a = 558-3
3×a = 555
a = 555 : 3
a = 185
a+1 = 186
a+2 = 187
verificare:
185 + 186 + 187 = 558
558 : 3 = 186