5 and 2 are the only prime numbers that end in a 5 or 2. A prime number is by definition only divisible by 1 and itself, and all other whole numbers ending in 5 or 2 are divisible by 5 or 2, respectively. Numbers that are not whole numbers cannot be prime.
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All numbers larger than 5 which end in 5 are divisible by 5 and so are not prime. All numbers larger than 2 which end in 2 are divisible by 2 and so are not prime.
Other than 2, no prime numbers are even. So prime numbers can't end in even numbers. After 5, no prime number can end in 5. After 5, all prime numbers end in 1, 3, 7 or 9.
Just 2 and 5
The prime numbers of 100 are: 2, 2, 5 and 5
2, 3, 5 are prime numbers but 9 is not a prime number