The result of adding 15 and 4 is:

$15 + 4 = 19$

Would you like more details, or do you have any questions?

Here are 5 related questions:

1. What is 19 minus 6?
2. What is 19 multiplied by 2?
3. What is the sum of 19 and 10?
4. If you subtract 4 from 19, what do you get?
5. What is 19 divided by 3?

Tip: When adding numbers, you can rearrange them in any order due to the commutative property of addition.