Kid-friendly explanation
When you add, each number you put together is an addend. In 3 + 5, the 3 is an addend and the 5 is an addend. They work together to make the sum, which is the answer, 8. You can have 2 addends, 3 addends, or even more addends in one problem!
Worked examples with addends
Example 1 (younger grades):
Look at this addition problem: 4 + 6 = ?
The addends are 4 and 6, because they are the numbers being added. Add the addends: 4 + 6 = 10. The sum is 10.
Example 2 (upper elementary):
Consider this problem with several addends: 27 + 15 + 8 = ?
The addends are 27, 15, and 8. First, add the ones: 7 + 5 + 8 = 20 ones, which is 2 tens and 0 ones. Regroup the 20 ones as 2 tens and 0 ones. Now add the tens: 2 tens (from 27) + 1 ten (from 15) + 0 tens (from 8) + 2 tens (regrouped) = 5 tens, or 50. So 27 + 15 + 8 = 50. The sum is 50, and all three starting numbers are addends.
Going deeper with addends
As problems get larger, your child will work with addends that have 2, 3, or even 4 digits, such as 3,482 + 219. The idea of an addend stays the same: every number being added is an addend, no matter how many digits it has.
Students also learn to add 3 or 4 addends, sometimes regrouping tens, hundreds, or thousands. They might look for friendly addends that make 10 or 100, such as 40 and 60, to make mental addition easier.
Later, your child uses unknown addends to solve subtraction and word problems. For example, in 14 − 9 = ?, they might think of it as 9 + ? = 14 and find the missing addend that makes the equation true.
Common mistakes with addends
- Mistake: Thinking only the first two numbers are addends in a longer problem, such as saying only 12 and 7 are addends in 12 + 7 + 5 = 24.
Correction: Every number that is being added is an addend, so 12, 7, and 5 are all addends in that equation. - Mistake: Mixing up the sum and the addends, for example saying that in 6 + 9 = 15, the 15 is an addend and 6 is the sum.
Correction: Addends are the numbers you add (6 and 9), and the sum is the answer you get (15). - Mistake: Losing track of one addend when adding several numbers, such as in 5 + 8 + 7, a child might add 5 + 8 = 13, then forget the 7 and say the answer is 13.
Correction: When there are 3 or more addends, each addend must be included in the total, so 5 + 8 + 7 = 20.
Everyday connection to addends
Addends show up any time your child puts groups together. If there are 3 apples in a bowl and 2 more apples are added, the 3 and the 2 are addends that make a sum of 5 apples. When keeping score in a game, each new set of points is another addend added to the total.