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Puzzles

8 December

It is possible to arrange 4 points on a plane and draw non-intersecting lines between them to form 3 non-overlapping triangles:
It is not possible to make more than 3 triangles with 4 points.
What is the maximum number of non-overlapping triangles that can be made by arranging 290 points on a plane and drawing non-intersecting lines between them?

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7 December

What is the obtuse angle in degrees between the minute and hour hands of a clock at 08:22?

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Tags: angles, clocks

6 December

The number n has 55 digits. All of its digits are 9. What is the sum of the digits of n3?

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5 December

The sum of 11 consecutive integers is 2024. What is the smallest of the 11 integers?

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Tags: numbers, sums

4 December

The geometric mean of a set of n numbers is computed by mulitplying all the numbers together, then taking the nth root.
The factors of 9 are 1, 3, and 9. The geometric mean of these factors is
$$\sqrt[3]{1\times3\times9}=\sqrt[3]{27}=3$$
What is the smallest number where the geometric mean of its factors is 13?

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3 December

There are 5 ways to write 5 as the sum of positive odd numbers:
How many ways are there to write 14 as the sum of positive odd numbers?

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Tags: numbers, sums

2 December

14 is the smallest even number that cannot be obtained by rolling two 6-sided dice and finding the product of the numbers rolled.
What is the smallest even number that cannot be obtained by rolling one hundred 100-sided dice and finding the product of the numbers rolled?

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Tags: dice

1 December

Eve writes down five different positive integers. The sum of her integers is 16. What is the product of her integers?

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