Copyright © University of Cambridge. All rights reserved.

'Number Balance' printed from http://nrich.maths.org/

Show menu


Full Screen Version
This text is usually replaced by the Flash movie.

This is a number balance.

number balance
It is also called a 'balance bar' or an 'equaliser'. It has weights:
weights
These are hung below the numbers. It balances equal numbers, for example like this:
balancing 10 on one side with 2 and 8 on the other
Where would you need to hang the weight to make the one below balance?
9=3+4+?
What about this one?
9+4=6+?
If you had to use two weights and make the one below balance, where could you put them?
9 and 6 on one side, 10 and 4 on the other
How many different ways can you make it balance with two weights?
You may like to use the interactivity above to explore the problem.