Advent calendar 2015

17 December

In March, I posted the puzzle One Hundred Factorial, which asked how many zeros 100! ends with.
What is the smallest number, n, such that n! ends with 50 zeros?


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 Most recent collections 

Sunday Afternoon Maths LXVII

Coloured weights
Not Roman numerals

Advent calendar 2018

Sunday Afternoon Maths LXVI

Cryptic crossnumber #2

Sunday Afternoon Maths LXV

Cryptic crossnumber #1
Breaking Chocolate
Square and cube endings

List of all puzzles


chocolate colouring angles sum to infinity means triangle numbers integers ellipses integration wordplay factorials shape routes menace proportion odd numbers dates coordinates trigonometry digits quadratics averages pascal's triangle scales lines partitions arrows probabilty logic advent money multiplication algebra division taxicab geometry perimeter time multiples prime numbers circles numbers factors calculus fractions square roots differentiation bases shapes polygons grids cards mean parabolas dice games doubling chalkdust crossnumber folding tube maps hexagons graphs area rugby books people maths cube numbers irreducible numbers coins squares star numbers volume triangles floors chess 3d shapes clocks dodecagons percentages complex numbers spheres cryptic clues regular shapes sequences unit fractions sums christmas functions geometry remainders crossnumbers cryptic crossnumbers number symmetry speed surds rectangles sport ave perfect numbers 2d shapes palindromes indices probability planes addition square numbers balancing crosswords


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© Matthew Scroggs 2019