Magic Crosses
Age 7 to 14 Challenge Level:
Can you find examples of magic crosses? Can you find all the possibilities?
Remainders
Age 7 to 14 Challenge Level:
I'm thinking of a number. My number is both a multiple of 5 and a multiple of 6. What could my number be?
Always a Multiple?
Age 11 to 14 Challenge Level:
Think of a two digit number, reverse the digits, and add the numbers together. Something special happens...
Which Is Cheaper?
Age 14 to 16 Challenge Level:
When I park my car in Mathstown, there are two car parks to choose from. Can you help me to decide which one to use?
Which Is Bigger?
Age 14 to 16 Challenge Level:
Which is bigger, n+10 or 2n+3? Can you find a good method of answering similar questions?
Exploring Cubic Functions
Age 14 to 18 Challenge Level:
Quadratic graphs are very familiar, but what patterns can you explore with cubics?
Shifting Times Tables
Age 11 to 14 Challenge Level:
Can you find a way to identify times tables after they have been shifted up or down?
Semi-regular Tessellations
Age 11 to 16 Challenge Level:
Semi-regular tessellations combine two or more different regular polygons to fill the plane. Can you find all the semi-regular tessellations?
Quad in Quad
Age 14 to 16 Challenge Level:
Join the midpoints of a quadrilateral to get a new quadrilateral. What is special about it?
Surprising Equalities
Age 14 to 18 Challenge Level:
Take any triangle, and construct squares on each of its sides. What do you notice about the areas of the new triangles formed?
Gibraltar Geometry
Age 11 to 14 Challenge Level:
Take a look at the photos of tiles at a school in Gibraltar. What questions can you ask about them?
Triangle Transformation
Age 7 to 14 Challenge Level:
Start with a triangle. Can you cut it up to make a rectangle?
NRICH is part of the family of activities in the Millennium Mathematics Project.