Question

Plz explain me this..how we do it

Answer 1

13000 because the 3 is under 5 and every number after that becomes 0 sorry I'm not the best at explaining

Answer 2

The number before the ten-thousands digit is what tells you whether or not you round up or down in this scenario. If it is greater than 5, then you round up. If it is less than 5, you round down. 3 is less than 5, so the answer is 13,000. 
Hope that helped.