Răspuns:
a:12=c₁ rest 7=>a=12c₁+7=>a-7=12c₁
a:18=c₂ rest 7=>a=18c₂+7=>a-7=18c₂
a:40=c₃ rest 7=>a=40c₃+7=>a-7=40c₃
12=2²·3
18=2·3²
40=2³·5
cmmmc (12;18;40) = 2³·3²·5 = 360
a-7=360=>a=360+7=>a=367
________
367:12=30 rest 7
367:18=20 rest 7
367:40=9 rest 7