When a secret agent wants to send a message, they write it in code so their enemies can't read it. Codebreakers need to develop mathematical skills like working backwards, being systematic, and ruling out possibilities in order to crack enemy codes and save the day. These problems will give you the chance to train your brain in order to become a better code cracker!
problem
Satisfying statements
Age
11 to 14
Challenge level
Can you find any two-digit numbers that satisfy all of these statements?
problem
Statement snap
Age
7 to 14
Challenge level
You'll need to know your number properties to win a game of Statement Snap...
problem
Charlie's delightful machine
Age
11 to 16
Challenge level
Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?
list
Hidden treasures
Age
11 to 16
Challenge level
Try these treasures to celebrate NRICH's birthday!