Number Series

Rules

1. A 3-second countdown, then the GO signal.
2. You see four numbers of a series, like «2, 4, 8, 16».
3. What comes next? Work out the rule and choose from three options.
4. You answer with the 1, 2 and 3 keys or by clicking the answer.
5. You get 1 min 15 s from the signal.

How scoring works

Every right answer scores, more the faster you answer, and every wrong one costs you.

Levels

• Gold level2,200 points
• Silver level1,400 points
• Bronze level700 points

Levels are earned by result; medals are only for the CCI Olympics.

Tips

• Look at the gap between consecutive numbers; if it is not fixed, try multiplying.
• When in doubt, rule out: the last digit is often enough to tell which one it is not.

Event ranking

See the full ranking