<P> An early reference to the rule is in the Summa de arithmetica ( Venice , 1494 . Fol. 181 , n . 44 ) of Luca Pacioli ( 1445 -- 1514 ) . He presents the rule in a discussion regarding the estimation of the doubling time of an investment , but does not derive or explain the rule , and it is thus assumed that the rule predates Pacioli by some time . </P>
<P> An early reference to the rule is in the Summa de arithmetica ( Venice , 1494 . Fol. 181 , n . 44 ) of Luca Pacioli ( 1445 -- 1514 ) . He presents the rule in a discussion regarding the estimation of the doubling time of an investment , but does not derive or explain the rule , and it is thus assumed that the rule predates Pacioli by some time . </P>
where did the rule of 72 come from
where did the rule of 72 come from
Summa de arithmetica of Luca Pacioli
Summa de arithmetica of Luca Pacioli