(a) 2205.
The prime factorization consist in finding prime numbers which multiplication gives the initial number, to find those prime numbers, we divide the number by 2, 3, or 5, depending on the case. Let's do it.
2205 | 5
441 | 3
147 | 3
49 | 7
7 | 7
1
So, the prime factorization is
[tex]2205=5\times3\times3\times7\times7[/tex](b) 2525.
Let's repeat the process as we did with (a).
2525 | 5
505 | 5
101 | 101
1
So, the prime factorization is
[tex]2525=5\times5\times101[/tex]