2.1. In the table, there are numbers. It turned out that six sums: three sums by rows and three sums by columns are the same. The minimum of the numbers $a, b$, and $c$ is 101. Find the sum $a+b+c$.

| $\mathrm{a}$ | 1 | 4 |
| :---: | :---: | :---: |
| 2 | $\mathrm{~b}$ | 5 |
| 3 | 6 | $\mathrm{c}$ |
Answer: 309

Solution. Note that $a+5=b+7=c+9$, therefore, the number $c$ is the smallest, and the others are 2 and 4 more, that is, 103 and 105. The sum of all three numbers $101+103+105=309$