mscroggs.co.uk
mscroggs.co.uk

subscribe

Puzzles

11 December

There are 6 sets of integers between 1 and 5 (inclusive) that contain an odd number of numbers whose median value is 3:
How many sets of integers between 1 and 11 (inclusive) are there that contain an odd number of numbers whose median value is 5?

Show answer

Tags: sets, medians

7 December

There are 8 sets (including the empty set) that contain numbers from 1 to 4 that don't include any consecutive integers:
\(\{\}\), \(\{1\}\), \(\{2\}\), \(\{3\}\), \(\{4\}\), \(\{1,3\}\), \(\{1,4\}\), \(\{2, 4\}\)
How many sets (including the empty set) are there that contain numbers from 1 to 14 that don't include any consecutive integers?

Show answer & extension

Tags: number, sets

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

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

Archive

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