| Can you find the missing number in the sequence given below?
11 15 19 12 16 ? 13 17 21 14 18 22 |
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You heard the travelers’ tales, you followed the maps, and now, you’ve finally located the dungeon containing a stash of ancient coins. The good news: the wizard who owns the castle has generously agreed to let you have the coins. The bad news: he’s not quite as generous about letting you leave the dungeon … unless you solve his puzzle. Can you solve it and get out alive? Lisa Winer and TED-Ed show you how.
| As shown in the image, the nine horses are fenced in a square. By constructing just two other square fences, can you make sure that two horses cannot meet each other without crossing the fence?
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| What’s the significance of twenty-three minutes (and 45 seconds) after one on the morning of June 7, 1989? | |
