Difficult Mathematical Challenges

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Displaying 31 level challenges Difficult: Remove Filter Challenge 8
On the old game board Challenge 17
Multiple 1998 Challenge 18
Straight Balls Challenge 19
Form the number 24 Challenge 24
Put the soldiers in rows Challenge 35
The Price of the Gift Challenge 43
How many eggs a year ??? Challenge 50
Divide wine among drunks Challenge 57
Cooking the Cookie Challenge 71
The Hungry Moth and the 10 Books Challenge 75
Represent Number 100 Challenge 76
Great-Grandfather's Age Challenge 83
Your Manoel Challenge Account 87
How old was Claudiomiro? Challenge 103
Correcting the expression with a dash Continues after advertising Challenge 105
Just Moving a Toothpick Challenge 108
The rooms and lamps Challenge 114
Eight Queens on the Chessboard Challenge 119
Beatriz Challenge 120's Early Watch
The Fire on the Rope Challenge 122
How much should the jeweler pay? Challenge 124
The Death Sentence Challenge 151
The Puzzle of Diophantus Challenge 160
Watermelon in the sun Challenge 162
Shaking Hands Challenge 163
The Cat, Coffee, and Cake Challenge 171
The False Cube Unfolded Challenge 176
Is there Friday 13 every year? Challenge 180
The Beggar and the Cigarettes Challenge 184
Painting the faces of a cube 1 2 Next >>

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