Ah, travelling from 八千代台(Yachiyo-dai) to 日暮里 (Nippori) you are taking Keisei line, not JR.
In that case, 定期券 for 1 month is JPY19,170, JPY54,640 for 3 months, JPY54,640 for 6 months.
These are costs for 通勤定期券 (tsuukin teikiken/season ticket for commuting), if you're going to school, you might be eligible for 通学定期券 (tsuugaku teikiken/same for students) which is much cheaper: JPY4,950/1 month, JPY14,000/3 months, JPY26,520/6 months.
Completely off-topic: I do love Maultauschen as well as Spaezle - I used to travel to Pleidelsheim (near Marbach and Freiberg) many times, and loved local food and wine! ;-)