mscroggs.co.uk
mscroggs.co.uk

subscribe

Puzzles

Two semicircles

The diagram shows two semicircles.
\(CD\) is a chord of the larger circle and is parallel to \(AB\). The length of \(CD\) is 8m. What is the area of the shaded region (in terms of \(\pi\))?

Show answer & extension

If you enjoyed this puzzle, check out Sunday Afternoon Maths LI,
puzzles about circles, or a random puzzle.

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

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

Archive

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