how to sum two numbers numbers are decimal values where each digit is ones or tens or hundreds etc. you know what numbers are! the simplest numbers to sum are the one digit numbers. people usually memorize these sums, or have personal tricks. until you develop this, one way is by counting, on your fingers, with physical objects, or preferably (practice to do this) in your head. the trick with summing is you count twice at the same time, so it can appear confusing at first, but it isn’t actually in the end, another approach is to combine the amounts and then count the result. but try to move toward doing it in your head! start with one number, and count up a number of times equal to the second number. the result is the sum of the two numbers!