After the success of last year’s event, the Global Mental Math Olympiad (GMMO) will return on 01–02 November 2025 in Dubai. It is organized by LiveMCL, who also run the Mental Math World Cup (online) each Summer.
This event is open to participants aged 6+ in three categories:
- Challenger (ages 6–8)
- Master (ages 9–11)
- Grandmaster (ages 12+)
Unlike most competitions, the tasks in the GMMO are multiple-choice. The tasks are also simpler than in other international competitions, making it more accessible to younger mental calculators. Here are some typical questions from the standard challenge:
- 208 – 56 + 36
- 29 × 19
- 65% of 700
- Half of 4518
- HCF of 91 and 63
- LCM of 45 and 75
- Exact square root of 4356
- Exact cube root of 91125
- Remainder of 45/7
- Prime factors of 567
Participants will use LiveMCL’s app during the competition. This means that results and leaderboards can be shared immediately.
There will be three categories:
- Everyone does the Standard Mandatory Challenge with a variety of calculation formats, on 01 November
- Optional additions and subtractions sprint
- Optional multiplications sprint
In addition, LiveMCL will open up their own book of world records, on 02 November. Participants at the event will have up to three opportunities to set a record in each of the following categories:
- Addition—2 digits (like 45 + 67)
- Addition—3 digits (like 345 + 678)
- Addition—4 digits (like 2345 + 6789)
- Mixed 2 digits ± 2 digits (like 82 – 34 or 82 + 34)
- Mixed 3 digits ± 2 digits (like 482 – 34 or 482 + 34)
- Multiplication—2 digits × 1 digit (like 34 × 8)
- Multiplication—2 digits (like 34 × 82)
- Multiplication—3 digits (like 345 × 824)
- Exact Square Roots—6 digits (like √207936)
To register, please read the information and follow the instructions on LiveMCL’s official website. The cost for registering is USD $100, plus a small fee for each optional challenge. Their website also contains study materials for all task categories. Registered participants can use their app for practising. Good luck!
If you have any questions about GMMO 2025, please contact the organizers LiveMCL by email (contact@livemcl.com) or by phone.
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