Solution to Blind Calculation
Answer: PRODUCT TESTING
by Evan Chen
As hinted by the title and the choice to have three beads per box, this is a puzzle about Braille. So, we need some way to convert the Japanese characters to Braille.
The correct choice is Japanese braille. The corresponding Braille dots then correspond to which beads to move on the abacus, yielding a two-digit number for each Japanese character, as shown in the table below.
Thus, for the left half of the abacus we get the following calculation.
We also get the following analogous calculation on the right half.
These numbers fit nicely in the red boxes provided, so we input those numbers into the abacus now. Taking the pink box into account (which clues to just mark the bottom dot in every row — something not possible using just the digits), and applying the process in reverse gives the following.
The answer seihin tesuto translates to the English phrase PRODUCT TESTING.