SUBIECTUL II: Determine the prime numbers $a, b, c$ for which:

$$
15 a+35 b+91 c=2015
$$
## SUBJECT II

| $5\|15 a ; 5\| 35 b ; 5 \mid 2015$ It follows that $5 \mid 91 c$ from which $c=5$ | $2 p$ |
| :---: | :---: |
| $15 a+35 b+455=2015$ |  |
| $15 a+35 b=1560$ | $2 p$ |
| $3 a+7 b=312$ |  |
| But $3\|3 a ; 3\| 312$. It follows that $3 \mid 7 b \Rightarrow b=3,3 a+21=312,3 a=291$ |  |
| $a=97$ |  |