100 Days of Puzzles
Challenging puzzles using logic, algebra, geometry, probability, and number theory. Do one puzzle a day for 100 days!
The Heavier Side
Count the Werewolves
Carrrs
Checkered Cubes
In Order or All at Once?
Find the Best Deal
Shaded Stars
Where's the Gold?
The Nine Nine Plus
Save Your Calculator
Venn Rectangles
On a Roll
A Lil Goes a Long Way
Striking Measure
Make a Ring of Sevens
Compare the Weights
How Hard Is It to Measure a Skyline?
Advances in Wolf Fence Design
How Did They Finish?
Make Them Inequivalent
Stack of Squares
In the Cards
Two Wrongs Make a Right
Werewolves Are Liars
There Are More Than Four Triangles!
How Much Faster Together?
The Star Area
Who is the Fastest Sprinter?
The Best Candidate
One More Flip
Inner and Outer Angles
Rearrange the Dots Again
Sock Hop
Go for the Gold
Fill the Diagonal
Pigeonholed Numbers
Did You Miss Any?
Two Triangles, One Trapezoid
Wandering Robots
Ha ha ha ha! Eh...
Draw the Line
Fill the Grid
Where Is the Gold?
Keep Coloring Forever
Should You Stop Rolling?
The Brilliant Hotel
Fish Fictions
There's a Quick Solution
Gears and Ants
How Many Werewolves?
Impossible Result
Add Up to Odd
Triangles in Line
Dice Wars
A's Abound!
Piece of a Circle
Crack the Code!
Running Round in Circles
Does It Change?
Stylish Socks
Can You Find Them All?
Red or Blue?
Human or Werewolf?
Only Multiply or Divide!
How Many Ways to Fill the Grid?
Yellow Plus Blue
Coins in Boxes
Mind Your Ps and Q
Does It Make a Cube?
Start in the Middle
Parallelogram and Circles
Misleading Marathoners
How Many Marbles?
Make Six Twice
Which Has More Faces?
How Much Will You Win?
Overlapping Areas
Taking Their Time
Diagonal Thinking
Knight, Knave, or Joker?
Cherry Production
Angle Hunt
The Short Pour
Exactly 3 Divisors?
Overlapping Rectangles
Shopping for Socks
It All Comes To Nothing
Humans and Werewolves
Only Two Pieces?
The Eye of...
What Makes Squares a Little Odd?
Perimeter from Perimeters?
Random Numbers
Too Many Twos
Octagons and Squares
What Color is Shinoy's Hat?
Elephant Ears
The Maximum Maximum
Course description
A 100-day puzzle-a-day challenge! Topics include: logic, algebra, geometry, probability, and number theory.
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Strategy Puzzles
Strategy puzzles using logic, probability, and number theory. Do one puzzle a day for a month!
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