You may also like

problem icon


This activity investigates how you might make squares and pentominoes from Polydron.

problem icon

Multilink Cubes

If you had 36 cubes, what different cuboids could you make?

problem icon

Cereal Packets

How can you put five cereal packets together to make different shapes if you must put them face-to-face?

Sealed Solution

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

A set of ten cards, each showing one of the digits from $0$ to $9$, is divided up between five envelopes so that there are two cards in each envelope. The sum of the two numbers inside it is written on each envelope:

five envelopes with the numbers 7, 8, 13, 14 and 3 written on them (one number per envelope)

What numbers could be inside the "8" envelope?

Thank you to Alan Parr for allowing us to adapt one of his problems.