Rounding
Replacing a number with a nearby simpler one to a chosen place value.
Key idea
Replacing a number with a nearby simpler one to a chosen place value.
In depth
Rounding replaces a number with a nearby simpler one. Look at the digit to the right of your target place: 5 or more rounds up, 4 or less rounds down. This keeps the answer close while simplifying.
Worked example
Round 3,468 to the nearest hundred: the tens digit is 6, so round up to 3,500.
Real-world uses
- Quoting population figures, prices to the nearest pound and estimated travel times in everyday speech
Common mistake
Rounding in stages. Always use the original digit, not an already rounded one.
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 Rounding?
Replacing a number with a nearby simpler one to a chosen place value. It is a topic at the beginner level in Arithmetic & Number Sense.
Where is Rounding used in real life?
Real-world examples: Quoting population figures, prices to the nearest pound and estimated travel times in everyday speech.
What should I learn before Rounding?
Make sure you are comfortable with Zero and Identity, the previous topic in Arithmetic & Number Sense.
What is a common mistake with Rounding?
Rounding in stages. Always use the original digit, not an already rounded one.
How can I practise Rounding?
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 Rounding?
Move on to Estimation 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.
- Ordering Numbers – Arranging numbers from least to greatest or the reverse.
- Even and Odd Numbers – Even numbers divide by 2 with no remainder; odd numbers leave remainder 1.