Question

The sum of my ones digit and tens digit is also 10. However, my ones digit is greater
than my tens digit. I am a prime number less than 30. What number am I?

Answer 1

really? There are only a few candidates:
19, 28, 37, 46
see any primes less than 30 in that list?

Answer 2

your number must be less than 30
if the unit digit and the tens digit add up to 10
your number is one of 28 or 19

Now, which of those is prime???