Maximum addition and subtraction sums of two-digit numbers in five minutes
The record for solving the maximum number of addition and subtraction sums of two-digit numbers was set by A. Adhi Dharshith (born on April 9, 2014) of Namakkal, Tamil Nadu. Using the Abacus method, he correctly wrote the answers of 84 two-digit (three rows) sums in five minutes, at the age of 7 years, 6 months and 14 days, as confirmed on October 23, 2021.