Partial SumsPartial Sums

An Addition AlgorithmAn Addition Algorithm

268+ 483600Add the hundreds (200 + 400)

Add the tens (60 +80) 140Add the ones (8 + 3)

Add the partial sums(600 + 140 + 11)

+ 11751

785+ 6411300Add the hundreds (700 + 600)

Add the tens (80 +40) 120Add the ones (5 + 1)

Add the partial sums(1300 + 120 + 6)

+ 6 1426

329+ 9891200 100

+ 18

1318

The partial sums algorithm for The partial sums algorithm for addition is particularly useful addition is particularly useful for adding multi-digit numbers. for adding multi-digit numbers. The partial sums are easier The partial sums are easier numbers to work with, and students numbers to work with, and students feel empowered when they discover feel empowered when they discover that, with practice, they can use that, with practice, they can use this algorithm to add number this algorithm to add number mentally.mentally.