Add 509 and 12:
509
+ 12
____
521
509 + 12 = 521
Step-by-step explanation:
- put your finger on zero and move it to -1 then go up to positive 1 and put ur dot there.
- put ur finger on 0 again then go to -1 but now u move down to -2 and put ur dot there.
- now put ur finger on the zero and go to the opposite side to positive 2 then go down to -2 and put ur dot there. Hope that helps :)
First answer is the correct answer
