Use knowledge of column addition and subtraction to calculate with decimal numbers
I can use knowledge of column addition and subtraction to calculate with decimal numbers.
Use knowledge of column addition and subtraction to calculate with decimal numbers
I can use knowledge of column addition and subtraction to calculate with decimal numbers.
Lesson details
Key learning points
- Numbers are recorded in columns with the same value digits in each column.
- Start with the smallest value column in case numbers need to be regrouped or exchanged.
- If the value of a digit in the minuend is greater than the same digit in the subtrahend, you will need to exchange.
- Make sure that any regrouped numbers are added in with others of the same value.
Common misconception
Pupils regroup incorrectly, particularly when subtracting e.g. exchanging one ten for ten ones.
Build the calculation using place value counters on a grid set out like a column method. Ask pupils to represent regrouping with counters.
Keywords
Decimal number - A decimal number has a decimal point followed by digits that show the fractional part.
Regrouping - The process of unitising and exchanging between place values is known as regrouping. For example: ten ones can be regrouped for one ten.
Place value - The value of a digit in a number based on where it is placed.
Licence
This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).
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Starter quiz
6 Questions
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Exit quiz
6 Questions
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