TOKYO, Dec 1 (Reuters) - Japanese government bond prices were mostly firmer on Tuesday after an auction of 10-year JGBs was greeted with ample demand, as expected by the market. The bid-to-cover ratio, a gauge of demand, at the 2.6 trillion yen ($24.91 billion) auction slipped to 3.42 from 4.13 at the previous sale in November, but remained near levels market participants consider as satisfactory. Benchmark 10-year JGB futures rose 0.06 point to 152.08, with a trading volume of 24,187 lots, while the 10-year JGB yield lost 1 basis point to 0.015%. In the super-long zone, the 20-year JGB yield inched down half a basis point to 0.390%. The 30-year JGB yield gained half a basis point to 0.650%, while the 40-year JGB yield stood flat at 0.695%. At the shorter end of the curve, the two-year JGB yield was unchanged at minus 0.130% while the five-year yield lost half a basis point to minus 0.110%. ($1 = 104.3800 yen) (Reporting by Tokyo markets team; Editing by Rashmi Aich) Our Standards: The Thomson Reuters Trust Principles.