# Which odd numbers are less than 20

## Even / odd numbers up to 20 and 50

We'll deal with even and odd numbers in this article. The following content is offered:

• One Explanation what are even and odd numbers and a listing for the numbers up to 20 and up to 50.
• Examples for even and odd numbers.
• Typical tasks and Exercises on this subject with sample solutions.
• A video area with a Videoexplaining even and odd numbers.
• A Question and answer area with typical questions on this topic.

In order to understand the following content, a few basics of mathematics are useful. If you are not familiar with the following topics, please read them up: Plus and minus tasks up to 20, counting in steps as well as doubling and halving. Everyone else can start right away with even and odd numbers.

### Even and odd numbers explanation

Let's take a look at what we mean by even and odd numbers. To do this, let's just start counting:

• 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24

Then they are divided as follows:

• Even numbers: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24
• Odd numbers: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23
Note:
• Even numbers end in 0, 2, 4, 6 or 8.
• Odd numbers end in 1, 3, 5, 7, or 9.
• A natural number is even if it can be divided by 2 without a remainder.

It is not difficult to distinguish between even and odd numbers. We just have to go to that Ones place pay attention and decide. In principle, the mnemonics from the previous box are sufficient for this. Many people in mathematics like to ask themselves the question: What do I need something like this for? A very simple application would be this:

The house numbers in many cities run alternately, so that even and odd numbers are each on one side of the street. The trick is based on the simpler continuation of the numbering when the street is later extended.

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### Even and odd numbers examples

In this section, we'll look at examples of even and odd numbers. On the one hand, these are examples to clarify the relationships, but also tasks such as pupils are given these in primary school.

example 1:

Name all even numbers up to 20 and up to 50, starting with zero.

Solution:

• Even numbers up to 20: 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20
• Even numbers up to 50: 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44 , 46, 48, 50

Example 2:

Name all odd numbers up to 20 and up to 50.

• Odd numbers up to 20: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19
• Odd numbers up to 50: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45 , 47, 49

Example 3:

Which of the following numbers are even numbers and which are odd numbers? 1, 5, 3, 2, 12, 17, 18

Solution: Even numbers are 2, 12, and 18. Odd numbers are all others: 1, 3, 5, 17

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### Even and odd numbers examples

In the next video, explanations of even and odd numbers are offered and numerous examples are also dealt with.

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### Even and odd numbers questions

In this section, we'll look at typical questions with answers about odd numbers and even numbers.

Q: Are there any books or software that deal with even and odd numbers?

A: Yes there is. For example "My big training book for maths 1st class" from Klett-Verlag.

Q: What other topics should I check out?

A: Here is a list of important basic math topics: