Vertical Addition by Partition with 2-digit Numbers 44 + 42 80 (40 + 40) Add the tens 6 (4 + 2) Add the units 86 Vertical Addition by Partition with 3-digit Numbers 549 + 424 900 (500 + 400) Add the hundreds 60 (40 + 20) Add the tens 13 (9 + 4) Add the units 973 |