From comparing this to the answers of others, I conclude that I am part abacus, as my method is to build tens out of small components, then consider the tens as a separate counter. #27plus48
@TQ Thank you. I'm more accustomed now to performing it over primes than in base 10, so it surprised me to see my own process. Glad you brought this to my attention.
From comparing this to the answers of others, I conclude that I am part abacus, as my method is to build tens out of small components, then consider the tens as a separate counter. #27plus48