- Who
- Scott Flansburg
- What
- 15 total number
- Where
- United Kingdom (Wembley)
- When
Scott Flansburg of Phoenix, Arizona, USA, correctly added a randomly selected two-digit number (38) to itself 36 times in 15 seconds without the use of a calculator on 27 April 2000 on the set of Guinness World Records in Wembley, UK.