89 Extractio de \({3 \over 4} 13\) de \({2 \over 5} 171\)

Et si \({3 \over 4} 13\) de \({2 \over 5} 171\) extrahere volueris, extrahe 275 de 3428; remanent 3153, que divide per ruptos: exibunt \({1~~6\phantom{0} \over 2~~10} 157\) pro residuo quesite
descriptio extractionis
3428 275
\({2 \over 5}\) 171 \({3 \over 4}\) 13
\({1~~6\phantom{0} \over 2~~10}\) 157
181 extractionis.

90 Quod residuum si rectum sit, ita per 7 cognoscitur: pensam182 de 275, que est 2, de pensa de 3428, que est 5, extrahe; residuum vero, quod est 3, habeas pro pensa de \({1~~6\phantom{0} \over 2~~10}\) 157. Possumus enim \({3 \over 4}\) 13 aliter de \({2 \over 5}\) 171 extrahere, videlicet ut extrahas 13 et \({3 \over 4}\)183 de 171; remanet \({1 \over 4}\) 157, cum quibus adde \({2 \over 5}\); erunt \({1 \over 4}\) \({2 \over 5}\) 157, hoc est \({1~~6\phantom{0} \over 2~~10}\) 157.

  • 181
    ⑤ (⑤:   om. F) ② (②:   om. F)
    descriptio extractionis (descriptio extractionis:   extractio S)
    3428 (3428:   3425 α   om. F) 275 (275:   om. F)
    \({2 \over 5}\) 171 \({3 \over 4}\) 13
    ③ (③:   om. α F R) \({1~~6\phantom{0} \over 2~~10}\) 157 (\({1~~6\phantom{0} \over 2~~10}\) 157:   om. F)
    (⑤:   om. F) (②:   om. F) (descriptio extractionis:   extractio S) (3428:   3425 α   om. F) (275:   om. F) (③:   om. α F R) (\({1~~6\phantom{0} \over 2~~10}\) 157:   om. F) :   om. V
  • 182pensam:   pensa R
  • 18313 et \({3 \over 4}\):   \({3 \over 4}\) 13 R

Liber Abbaci

Instrumenta

Capitulum septimum

Indice