mscroggs.co.uk
mscroggs.co.uk

subscribe

Advent calendar 2019

2 December

You have 15 sticks of length 1cm, 2cm, ..., 15cm (one of each length). How many triangles can you make by picking three sticks and joining their ends?
Note: Three sticks (eg 1, 2 and 3) lying on top of each other does not count as a triangle.
Note: Rotations and reflections are counted as the same triangle.

Show answer

Archive

Show me a random puzzle
 Most recent collections 

Advent calendar 2024

Advent calendar 2023

Advent calendar 2022

Advent calendar 2021


List of all puzzles

Tags

calculus money unit fractions tangents chalkdust crossnumber planes ellipses geometric means scales colouring digits albgebra proportion floors sport routes remainders chess axes squares speed gerrymandering 2d shapes digital clocks palindromes cards averages algebra taxicab geometry symmetry addition dates factorials determinants numbers geometry consecutive numbers square grids elections sets coins folding tube maps range digital products cubics triangles multiples polygons rectangles doubling integers quadrilaterals games menace means christmas ave powers parabolas division balancing prime numbers logic mean tiling median volume sums circles spheres dodecagons complex numbers decahedra advent area tournaments sum to infinity time probability irreducible numbers polynomials fractions integration people maths graphs multiplication probabilty shapes quadratics cryptic crossnumbers perimeter books crossnumbers trigonometry coordinates hexagons geometric mean indices cryptic clues wordplay differentiation neighbours the only crossnumber pentagons crosswords dominos surds square numbers matrices expansions factors sequences functions partitions odd numbers rugby pascal's triangle products crossnumber chocolate binary arrows triangle numbers cube numbers dice percentages bases number medians regular shapes square roots grids shape lines 3d shapes angles even numbers consecutive integers clocks star numbers perfect numbers combinatorics numbers grids

Archive

Show me a random puzzle
▼ show ▼
© Matthew Scroggs 2012–2025