Play word 鶴亀算 鶴亀算 つるかめざん obtaining the respective numbers of cranes and tortoises from the total of their heads and legs
Play word 日本国有鉄道清算事業団 日本国有鉄道清算事業団 にほんこくゆうてつどうせいさんじぎょうだん Japanese National Railways Settlement Corporation
Play word 百マス計算 百マス計算 ひゃくマスけいさん method of learning through repetition which involves multiplying and other calculations carried out on a 10-by-10 grid of numbers