Mentally adding hundreds to 3-digit numbers
Your child can add or take away hundreds in their head, like 342 + 200 or 756 − 300. They know only the hundreds digit changes.
In curriculum terms
Mentally add and subtract a three-digit number and hundreds
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How to tell they’ve got it
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Try this together
Can your child quickly work out '342 + 200' or '756 − 300' in their head — knowing that only the hundreds digit changes?
Where this sits on the map
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Curriculum alignment
Where this fits in the official school curriculum — our best automated guess, not yet checked by a person.
Show candidate curriculum codes · 3 ACARA · 2 NSW · 3 VIC
Australian Curriculum v9 candidate
add and subtract two- and three-digit numbers using place value to partition, rearrange and regroup numbers to assist in calculations without a calculator
add and subtract one- and two-digit numbers, representing problems using number sentences and solve using part-part-whole reasoning and a variety of calculation strategies
extend and apply knowledge of addition and subtraction facts to 20 to develop efficient mental strategies for computation with larger numbers without a calculator
NSW syllabus codes & stages only
Victorian Curriculum 2.0 codes & levels only
These are candidate alignments generated by semantic matching — machine-suggested and unreviewed (v0.1), not official or verified mappings. For official curriculum content see australiancurriculum.edu.au, curriculum.nsw.edu.au and f10.vcaa.vic.edu.au. Don’t rely on them for registration or compliance purposes.