Addition and subtraction

Crosses can be drawn on number grids of various sizes. What do you notice when you add opposite ends?

How much lighter will £5 worth of 5p's be with these new lighter coins?

How far apart are the first and last bus stops in this bus route?

Arrange these three famous mathematicians in order with the shortest-lived first.

How many of the numbers 1 to 20 are not the sum of two primes?

Tony and Tina can't work out which of them owes what to the other. Can you?

Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.

Can you solve this magic square?

An old game but lots of arithmetic!

Investigate the different distances of these car journeys and find out how long they take.