Vertical Addition by Partition with 2-digit Numbers 44 + 64 100 (40 + 60) Add the tens 8 (4 + 4) Add the units 108 Vertical Addition by Partition with 3-digit Numbers 272 + 859 1000 (200 + 800) Add the hundreds 120 (70 + 50) Add the tens 11 (2 + 9) Add the units 1131 |