![[New!]](../images/new.gif){kind=small}
Turning Cards ★★Guess What ★★Thoughtless Thief ★★Tick-Tack-Toe ★★The Round Table ★★Happy Handshaking ★★Lighting Bulb ★★Apples and Pears ★★Fun with Fuses ★★Family Fuss ★★★ Chessboard Chunks ★★★ Wagon Works ★★★ Little Lies ★★★ Square Circles ★★★ Placing Bricks ★★★ Troubled Traveler ★★★ Barbara's Boxes ★★★ Alien Alert ★★★ At School ★★★ Because the water lily doubles its size every day and the complete pool is covered after 20 days, half of the pool will be covered one day before that, after 19 days.
Conclusion: after 19 days, the water lily will cover half of the pool.
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