Another in our series of adding decimals mentally, suitable for year 5 children. A good understanding of place value and decimals is needed for this, especially for the second set of questions.
Look out for a common error. For example: 0.3 + 0.48 answered as 0.51. In this case the 0.3 has been thought of as 0.03 and added to the hundredths when it should be added to the tenths, so the correct answer is 0.78.
We are looking for quick responses to these types of question. If children are taking a long time over them it might be because they have not learned their addition facts to 10 sufficiently so that they still need to count on to work the answers out.
Further similar pages to this can also be found in our Four Rules section.
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