An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.
Choose any three by three square of dates on a calendar page...
Can you make a tetrahedron whose faces all have the same perimeter?
The diagram shows three touching circles each of radius $5$cm and a line which touches two of them.
Find, in terms of $\pi$, the total perimeter of the two shaded shapes.
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
This problem is taken from the UKMT Mathematical Challenges.View the archive of all weekly problems grouped by curriculum topic