Two rivals race opposite ways around a circular railway
In Lewis Carroll's 'A Tangled Tale,' an aunt and her niece each board a train circling the same loop line in opposite directions — one direction takes 3 hours to complete the circuit, the other 2 hours, and a train leaves each way every 15 minutes. They bet on who will pass more oncoming trains before reaching home. Who wins?
Reveal the answer
Neither — it's a dead tie. Working out the timing shows each traveler meets exactly 19 oncoming trains during their trip, no matter which direction they picked. The aunt, tellingly named 'Mad Mathesis,' had rigged a bet that couldn't be won or lost. From Lewis Carroll's A Tangled Tale, Knot III: 'Mad Mathesis' (serialized in The Monthly Packet, 1880-1885).
— Lewis Carroll, A Tangled Tale — Knot III, "Mad Mathesis" (serialized in The Monthly Packet, 1880-1885; collected 1885)
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