Mastering Adding and Subtracting Decimals for 11+ Maths
19 October 2026
Why decimals matter in 11+
Adding and subtracting decimals is a key skill tested in the 11+ maths exam. These questions check your child's understanding of place value and their ability to calculate accurately. Mistakes often happen when decimal points are not lined up, so practising this area helps build accuracy and confidence.
Lining up decimal points
When working with decimals, always line up the decimal points before adding or subtracting. This keeps tenths, hundredths and other digits in the correct columns. For example, write 4.38 + 2.7 as:
4.38 +2.70
Adding zeros where needed makes calculations clearer and helps avoid errors.
Tips for parents
Encourage your child to use lined or squared paper to keep their numbers neat. Ask them to say their method out loud and check their answers by estimating. Using real-life examples, such as money or measurements, can make decimals more meaningful.
Key insight: Practising on squared or graph paper helps children keep decimal points aligned and reduces careless mistakes.
Building confidence with practice
Regular, focused practice on adding and subtracting decimals is the best way to improve. Start with simpler questions and build up to more challenging ones. Remind your child to work carefully, check their answers, and not to rush. Consistent effort pays off in the exam.
