Ordering Numbers
Arranging numbers from least to greatest or the reverse.
Key idea
Arranging numbers from least to greatest or the reverse.
In depth
Ordering is repeated comparison. Find the smallest (or largest), set it aside, and repeat. Equivalent to placing every number on a number line and reading left to right.
Worked example
Order 52, 25, 205: lengths first, 25 and 52 have 2 digits, 205 has 3 so it is largest. Then 25 < 52. Result: 25, 52, 205.
Real-world uses
- Ranking race times
- Sorting a list of prices
- Arranging house numbers or file names in sequence
Common mistake
Comparing digit by digit from the right. Always start from the highest place value.
How to learn this
- Read the key idea and say it in your own words.
- Work through the worked example, then try a similar problem.
- Use the interactive lesson’s visual and mini-quiz to check the pattern.
Frequently asked questions
What is Ordering Numbers?
Arranging numbers from least to greatest or the reverse. It is a topic at the beginner level in Arithmetic & Number Sense.
Where is Ordering Numbers used in real life?
Real-world examples: Ranking race times; Sorting a list of prices; Arranging house numbers or file names in sequence.
What should I learn before Ordering Numbers?
Make sure you are comfortable with Comparing Numbers, the previous topic in Arithmetic & Number Sense.
What is a common mistake with Ordering Numbers?
Comparing digit by digit from the right. Always start from the highest place value.
How can I practise Ordering Numbers?
Open the interactive lesson, play with the visual, then answer the three-question mini-quiz. Getting two right marks the topic complete.
What comes after Ordering Numbers?
Move on to Even and Odd Numbers next.
Related beginner topics in Arithmetic & Number Sense
- Counting & Cardinality – Assigning one number word to each object to find how many there are.
- Place Value – The value of a digit depends on its position: ones, tens, hundreds and so on.
- Number Line – A line where numbers are placed in order at equal spacing to compare and add them.
- Comparing Numbers – Use <, > and = to say which number is smaller, larger or equal.
- Even and Odd Numbers – Even numbers divide by 2 with no remainder; odd numbers leave remainder 1.
- Skip Counting – Counting forward by a fixed step such as 2s, 5s or 10s; the root of multiplication.