Equal as balance – Equalities & inequalities (static)
Referring to the picture above, four yellow balls and eight green balls are put together in one part of the weight-balancing. While, the other part of the weight-balancing contains only three yellow balls that make, which is unbalance with the total 12 balls. In order to make it balance, another 12 balls are required in the second part of the weight-balancing.
4 + 8 = 3 + 9
Thus, another nine green balls are needed to make the weight-balancing in balance.
