S. Samith (born on September 1, 2014) of Andhra Pradesh, India, is titled as ‘Grand Master’ for solving 150 single digit additions in one minute using Abacus method. He mentally added 150 single digit numbers non-stop for one minute (with a time gap duration of 0.4 seconds) and answered correctly using the Abacus method, at the age of 6 years and 9 months, as confirmed on June 9, 2021.