Bezeichne die gesuchte Anzahl mit N. Die gegebenen Informationen liefern
(1) N ∈ {401,404,407,410,413,416,419,422,425,428,431,434,437,440,443,446,449}
(2) N ∈ {403,407,411,415,419,423,427,431,435,439,443,447}
(3) N ∈ {401,406,411,416,421,426,431,436,441,446}
Also ist N = 431.