Mentally adding hundreds to 3-digit numbers
Mentally add and subtract a three-digit number and hundreds
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Teaching Table
Set out your lesson
“Can your child quickly work out '342 + 200' or '756 − 300' in their head — knowing that only the hundreds digit changes?”
Full guide and materials
- Activity. Mentally add and subtract a three-digit number and hundreds
What to notice. Calculate 345 + 200 mentally • Calculate 762 − 400 mentally • Explain that only the hundreds digit changes
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Can your child quickly work out '342 + 200' or '756 − 300' in their head — knowing that only the hundreds digit changes?
Mentally add and subtract a three-digit number and hundreds
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Check understanding
- Calculate 345 + 200 mentally
- Calculate 762 − 400 mentally
- Explain that only the hundreds digit changes
“Can your child quickly work out '342 + 200' or '756 − 300' in their head — knowing that only the hundreds digit changes?”
Curriculum record
- Type
- Procedural
- Subject
- Mathematics
- Domain
- Addition & Subtraction
- Age range
- Ages 7–8
Standards