_____ _____ _____ _____
| a | | 18 | | 75 | | 85 |
|____| |____|____________________ |____| |____|
|
=>a+18=75+85
a=(75+85)-18
a=160-18
a=142
=> 142+18=75+85
160=160.....( astfel balanta se afla in echilibru)
_____ _____ _____ _____
| 125 | | 65 | | 75 | | c |
|____| |____|________________________ _|____| |____|
|
=> 125+65=75+c
c=(125+65)-75
c=190-75
c=115
=> 125+65=75+115
190=190.......( balantele sunt in echilibru)