How it works
Pick a type of question and a difficulty, then press Start. You have 60 seconds. Each correct answer scores 10 points, and every answer in a row adds a streak bonus. A wrong answer or a skip resets your streak, but it never costs points.
Four mental maths shortcuts
- Percentages: find 10% by moving the decimal point. Half of that is 5%, and 15% is 10% plus 5%.
- Times 9: multiply by 10 and subtract the number. For 9 × 7, do 70 − 7 = 63.
- Times 11: for a two-digit number, add its digits and put the total in the middle. 23 × 11 = 253.
- Squaring a number ending in 5: multiply the first digit by the next digit up, then write 25. For 35², do 3 × 4 = 12, so 1225.
Practising for a few minutes a day builds speed. Take a break with a Sudoku puzzle when you are ready.