- Who
- Rikako Miyamoto
- What
- 1.61 second(s)
- Where
- Japan (Nakano)
- When
The fastest mental arithmetic (15 sets of three-digit numbers) – Flash Anzan™ is 1.61 seconds and was achieved by Rikako Miyamoto (Japan) by correctly adding 15 sets of three-digit numbers flashed on the screen in Nakano, Tokyo, Japan, on 18 February 2024.
Rikako shortened the previous record of 1.62 seconds by 0.01 second. She achieved this record at the 72nd Nakano Abacus Competition.