You add 424 to 159. First you add 9 and 4, which gives you 13 so add ONLY the three to the bottom and carry the 1 and place it above the 2 in 424. Then, add 5 and 2, which gives you 7, but since you carried a 1, you add 7 and 1, which gives you 8. Lastly, you add the 4 and the 1, which gives you 5. And you got your answer, 583.
