Adding And Subtracting Decimals Worksheets

Adding and subtracting decimals at a glance

If a number has a part that is not whole, it is called a decimal number. We write the whole number part, followed by a decimal point, then tenths, hundredths, thousandths, and so on. It is important that students can recognise the decimal place value of each column on a place value chart – for example, know that 0.6 represents 6 tenths. Ordering decimals also requires students to apply this knowledge of place value.

Decimal addition follows the same method as integer addition. We write the numbers in columns according to their place value: units under units, tens under tens and so on. The decimal points should be lined up, as should the values (tenths, hundredths etc) after the decimal points, and any gaps filled with zeroes. Working from the column furthest right (so with the smallest place value), add each column of digits, carrying into the next column if necessary.

To carry out a decimal subtraction, we line up the numbers as described for addition, ensuring that the first number in the calculation is on the top. We then subtract each column of digits, borrowing from the next column if needed as we would in integer subtraction.

These skills are then extended further to dealing with decimal multiplication and decimal division, including long division methods.

Looking forward, students can then progress to additional number worksheets, for example an order of operations worksheet or a fraction subtraction worksheet.

For more teaching and learning support on Number our GCSE maths lessons provide step by step support for all GCSE maths concepts.