57 De cantare¹¹⁰

Item cantare cuiuslibet mercis valet libras 14 et soldos 7; quantum valent ergo rotuli 37 eiusdem mercis? Fac de soldis 7 partes unius libre; erunt \({7 \over 20}\), quas¹¹¹ pone post 14 sic: \({7 \over 20}\) 14.

287 ℞ 12 \({7 \over 20}\) 14 100 ⑥   \({\phantom{1}8~~\phantom{1}2~~\phantom{1}2~~\phantom{1}6 \over 10~~10~~12~~20}\) 5 37

¹¹² Et describe questionem et multiplica \({7 \over 20}\) 14 per 37 que sunt ex adverso et divide per 100, hoc est multiplica 14 per 20; desuper¹¹³ adde 7 que sunt super 20: erunt soldi [R:61v] 287, quos pone super \({7 \over 20}\) 14, et multiplica eos¹¹⁴ per 37: erunt 10619, que debet dividere per 100 et per¹¹⁵ 20 de virgula. 58 Sed cum 12 in virgula divisionis nos habere oporteat, ut habeamus¹¹⁶ in una multiplicatione [V:36r] libras et soldos et denarios, multiplica 10619 per ipsa 12 et divide per 100 et per \({\phantom{1}1~~\phantom{1}0 \over 12~~20}\), hoc est per \({\phantom{1}1~~\phantom{1}0~~\phantom{1}0~~\phantom{1}0 \over 10~~10~~12~~20}\); exibunt libre \({\phantom{1}8~~\phantom{1}2~~\phantom{1}2~~\phantom{1}6 \over 10~~10~~12~~20}\)¹¹⁷ 5 pro pretio dictorum rotulorum 37, quorum pensa est 6 per novenarium.