Question

How to add 509+12 and get the answer to it

Answer 1

So basically you can add it with column addition or just simply break it down

Think about it lets break down 12 i got 10 and 2
then you can add it more easily

you could do 5019+10=519
then add 2 to get 521

Or you could do this

509
  12 +
______
521

so basically toy add 9+2 to get 11
then you carry the 1
then you do 1+1=2
then the 5 is left

so finally you get left with 512

You always work from left to right

Answer 2

Add 509 and 12:
509
+ 12
____
521
509 + 12 = 521