Sign Up
School Account Sign Up
Contributor: Meghan Vestal. Lesson ID: 11295
In addition to knowing if a number is odd or even, you can predict if the sum of two large numbers will be odd or even in addition! Learn and practice the secret with a new worksheet and online quiz!
Without solving the problem, determine whether the sum will be even or odd:
31,622 + 98,868 =
In the first Related Lesson of this series, found in the right-hand sidebar, you learned what makes a number even or odd.
On a separate piece of paper, write down two ways to determine if a number is even and two ways to determine if a number is odd. Check over your list with a teacher or parent.
If you are having trouble remembering what classifies a number as even or odd, go back and review this Related Lesson before moving forward. You will need to know what makes a number even or odd to complete this lesson.
In this lesson, you will learn a few tricks for identifying whether a sum or difference will be even or odd.
The rules for knowing whether a sum will be even or odd are:
|
even + even = even |
6 + 4 = 10 |
|
odd + odd = even |
9 + 3 = 12 |
|
odd + even = odd |
5 + 4 = 9 |
|
even + odd = odd |
2 + 7 = 9 |
The same rules apply for subtraction:
|
even - even = even |
6 - 4 = 2 |
|
odd - odd = even |
9 - 3 = 6 |
|
odd - even = odd |
5 - 4 = 1 |
|
even - odd = odd |
8 – 5 = 3 |
Being able to guess whether a sum or difference will be even or odd is a fun trick!
Move on to the next section to try it out.
Supplies
Related Lessons
FAVORITE
Like