Expanded form decimals explained for 11+ maths
21 October 2026
What is expanded form for decimals
Expanded form shows the value of each digit in a number. For decimals, this means breaking the number down into each digit's place value. This is an important skill for 11+ maths, as it helps children understand how decimals work and compare them confidently.
Why expanded form matters in 11+ maths
Understanding expanded form helps children see the value of every digit, even those after the decimal point. This knowledge is often tested in 11+ questions, especially when comparing or calculating with decimals.
Key insight: Writing decimals in expanded form makes it much easier to spot place value mistakes and check calculations. It also builds a strong foundation for more advanced maths topics.
Worked example
Let's write 3.42 in expanded form.
First, look at the digit before the decimal point. The 3 is in the ones place, so its value is 3.
Next, look at the first digit after the decimal point. The 4 is in the tenths place, so its value is 0.4.
Then, look at the second digit after the decimal point. The 2 is in the hundredths place, so its value is 0.02.
So, 3.42 in expanded form is 3 + 0.4 + 0.02.
The correct answer is 3 + 0.4 + 0.02.
How to practise expanded form decimals
Encourage your child to break down different decimals in this way. Start with simple numbers and gradually include more decimal places. This practice will help them become more confident for the 11+ exam.
