a : 4 = x rest 3 ==> a = 4x+3=>x = (a-3)/4
a : 10 = y rest 1 ==> a = 10y+1=>y=(a-1)/10
a : 12 = z rest 3 ==> a= 12z+ 3=>z=(a-3)/12
x + y + z = a/3 + 16
(a-3)/4 + (a-1)/10 + (a-3)/12 = a/3 + 16 |×60
15(a-3) + 6(a-1) + 5(a-3) = 20a + 960
15a-45+6a-6+5a-15 = 20a + 960
26a - 20a = 960 + 66
6a = 1 026
a = 1 026 : 6
a = 171
Verificare:
171 : 4 = 42 rest 3
171 : 10 = 17 rest 1
171 : 12 = 14 rest 3