What is column addition?

When writing down sums, separate the numbers into ones, tens, hundreds and thousands. List the numbers in a column and always start adding with the ones first.

  • Estimate first and check afterwards - it's a good idea to estimate a rough answer first and then check your actual answer.
  • Order doesn't matter - remember that 345 + 129 is the same as 129 + 345.
  • Key words - look out for these words in problems: total, sum, altogether, more. They all indicate an addition calculation.
jerry standing next to a sum
When adding together 345 + 129, you should write it down like this.