The dozen is convenient because its multiples and divisors are convenient : NUMBER@1 = NUMBER@2 & times ; NUMBER@2 & times ; NUMBER@3 , NUMBER@3 & times ; NUMBER@4 = NUMBER@2 & times ; NUMBER@5 , NUMBER@6 = NUMBER@1 & times ; NUMBER@7 , NUMBER@8 = NUMBER@1 & times ; NUMBER@9 .

The dozen is convenient because its multipliers and multiples are convenient : NUMBER@1 = NUMBER@3 & times ; NUMBER@2 & times ; NUMBER@2 , and NUMBER@8 = NUMBER@9 & times ; NUMBER@1 .
