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Code to Zero
problem

Code to zero

16 to 18
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Find all 3 digit numbers such that by adding the first digit, the square of the second and the cube of the third you get the original number, for example 1 + 3^2 + 5^3 = 135.
Corner Cut
problem

Corner cut

11 to 14
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Weekly Problem 23 - 2017
Three small equilateral triangles of the same size are cut from the corners of a larger equilateral triangle. What is the side length of the small triangles?
Totality
problem
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Totality

5 to 11
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This is an adding game for two players. Can you be the first to reach the target?

Evidence and Headlines
article

Evidence and headlines

11 to 18

Headlines sometimes distort the truth. Read about how micromorts can be used to compare the risks of different activities.

Picture Story
problem
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Picture story

14 to 16
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Can you see how this picture illustrates the formula for the sum of the first six cube numbers?

How Many Miles To Go?
problem
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How many miles to go?

11 to 14
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How many more miles must the car travel before the numbers on the milometer and the trip meter contain the same digits in the same order?

Ishango bone
problem

Ishango bone

7 to 18
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Can you decode the mysterious markings on this ancient bone tool?
Diagonal Sums
problem
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Diagonal sums

7 to 14
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In this 100 square, look at the green square which contains the numbers 2, 3, 12 and 13. What is the sum of the numbers that are diagonally opposite each other? What do you notice?

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