Algebra Four Pan Balance

Use this unique balance to physically show the sum of an integer and its additive inverse is zero.

Unlike any other balance, this one makes it possible to physically show that –1<0. Weights placed on the outer pans represent negative integers and those placed on the inner pans represent positive integers.

When you place a weight in each pan on one side of the centre post, the balance remains level as (–1)+(+1)=0. Great for small group work, the balance comes with four plastic pans, four plastic canisters, a set of plastic weights and a Teacher’s Booklet. Some assembly required