Today's PUZZLE CLASSIC OF THE DAY
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A Crystal
Place the numbers 1-12, sans 9, into the "atoms" of this crystal lattice so that each row totals 20. Two additional numbers are already placed in it - 5 and 15.
How Many Pentagons?
How many different pentagons are in this shape?
A 16-cell Part into 4 Chambers
Cut this figure into four congruent parts, each of which would contain two screws and one opening.
Kite: How Many Triangles?
How many triangles (one or more segments) can you count in this image?
Four Brothers - Sum of Ages
There are four brothers in a family. The sum of the ages of each combination of three brothers: 30, 32, 32, and 35. How old is the oldest brother?
Maximum Multiplication
What is the largest number that can be made by multiplying two three-digit numbers together using each of the digits from 1 to 6 exactly once? Example: 134 × 256 = 34,304, though this is not the largest number that can be made. What is?
Guess the Number: 1 to 100
Turn off the numbers until you end up with only one number.
Behind Each Other
Sierra is standing behind Giselle. And Giselle is standing behind Sierra. This doesn't seem possible but it is. How?
Four 9's and a 1 to 100
Arrange four 9's and a 1, and ONLY ONE basic arithmetic operator (-, +, /, or x) into a mathematical expression with a result equal to 100. NOTE: All 5 numbers must be used (e.g. 99 + 1 is not valid).
Covering the Hole
It is possible to cut a 3x6 slab into two pieces so that when re-arranged they can neatly fit into the 2x9 hole. Can you do that?
Eight 8's to a Thousand
How can you add eight 8's to make 1,000? How many pluses would you use for this?
Four 4's Into Seven
Using four 4's and basic math operations (addition, subtraction, multiplication, and division), reach number 7. NOTE: you are not allowed to combine digits.