All cases
Two Guards, One Question★☆☆about 4 min
Twelve Coins, Three Weighings★★★about 8 min
The Clock in the Mirror★☆☆about 3 min
The Missing Dollar★☆☆about 4 min
Footprints in One Direction★★☆about 5 min
Three Switches, One Bulb★★☆about 5 min
Cutting a Gold Bar Twice★★☆about 5 min
Three People, Five Hats★★★about 8 min
Checking the Four Cards★★★about 6 min
Three Doors and a Detective★★☆about 5 min
The Dog That Did Not Bark★☆☆about 4 min
Glass Scattered Outside★☆☆about 3 min
Measuring a Building by Its Shadow★★☆about 4 min
Thirteen People, Same Birth Month★☆☆about 3 min
The Die That Cannot Exist★☆☆about 3 min
The Round-Trip Average Speed★★☆about 5 min
Over the Weight Limit★★☆about 5 min
Three Things Across the River★☆☆about 5 min
Two Taps and a Tank★☆☆about 4 min
The Twenty-Minute Head Start★★☆about 5 min
Twenty Percent Off, Then Ten Percent Up★☆☆about 3 min
Across the Round Table★☆☆about 3 min
Forty-Five Minutes from Two Ropes★★★about 8 min
Nine Minutes from Two Hourglasses★★☆about 6 min
Twenty-Three People★★☆about 5 min
Counting Coins by Remainders★★☆about 6 min
Ten Heaps, One Weighing★★★about 8 min
The Magic Square Lock★☆☆about 4 min
Three-Cent and Five-Cent Stamps★★☆about 5 min
The Gap Under the Door★★☆about 5 min
Moving the Bolt★★☆about 5 min
Poison Hidden in the Ice★★☆about 5 min
The Missing Newspapers★☆☆about 3 min
Socks in the Dark★☆☆about 3 min
The Four-Lamp Code★☆☆about 4 min
The Shifted Note★☆☆about 4 min
A Sixty-Four Player Tournament★☆☆about 3 min
Three Cuts Through a Cake★★☆about 5 min
What Day Is the Thirteenth?★★☆about 4 min
The Genuine Barcode★★★about 8 min
Three Sticks, One Triangle★★☆about 4 min
The Diagonal of a 3 by 4 Room★☆☆about 4 min
Four Statements, One Culprit★★★about 10 min