Hi, Sthefy! This is just a little bit of adding, not too hard! Okay, 5 tens. What is 1 ten equal to? 10!
2 tens? 20!
3 tens? 30!
You get the idea? Okay, so now we know that 5 tens are 50. Now, ones. All we need to do now is add 13 + 50! Let's break it down, make it easier.
13.. Hm, what can we do to make this easier?
Ah! Take away the 3 from 13 for now. So just 10 + 50. That's 60. Now, add the 3. 63! That wasn't hard, was it? I hope I helped you!