# Worksheet: Identifying Odd and Even Numbers: Additon Sentences

In this worksheet, we will practice writing expressions of the form a+a or a+a+1 to prove whether a number up to 20 is even or odd.

**Q2: **

Let us think about even numbers. 2, 4, 6, 8, and 10 are examples of even numbers. Notice that they are all doubles.

Which of the following sums has an answer that is an even number?

- A8 + 8
- B8 + 8 + 1

**Q3: **

State whether the answer to the sum is even or odd: .

- Aeven
- Bodd

**Q4: **

Ethan has drawn this picture to show that 16 is an even number.

His teacher asks him to complete the addition sentence that shows that 16 is even.

He knows that he needs to write the same number in both boxes. What number is this?

**Q6: **

If a number is **odd**, then we can divide it into two equal groups with one left over.
This means that every odd number can be written as an addition sentence that is a doubles fact plus one.

For example, we know that 11 is odd because .

Which of these addition sentences shows that 9 is odd?

- A
- B
- C
- D