You will be given a definition of a task first, then some input of the task.
In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.

Passage: In 985 Otto III appointed him to succeed Margrave Rikdag in Meissen, following severe Saxon setbacks against the Slavic Lutici tribes during the Great Slav Rising. Eckard remained a vital support for the king and his mother Empress Theophanu. His military responsibilities consisted primarily of securing the Milceni lands as well as the containment of the neighbouring Polish and Bohemia duchies. Duke Boleslaus II of Bohemia had allied with Duke Henry and had taken the occasion to occupy the Albrechtsburg residence, he nevertheless had to withdraw by 987, after Eckard's forces had prevailed. According to the chronicles of Thietmar of Merseburg, he was later elected Duke of Thuringia by the magnates of the region, an event which has been taken as evidence of the principle of tribal ducal election.
Link Information: none Question: How old was Rikdag when Eckard I, Margrave of Meissen was appointed to succeed him?
Output:
Answer: none