SME
Grade 2 Math · Problem type
Broken ruler
Use this when the object doesn’t start at 0 on the ruler.
Picture
Starts at 3 cm, ends at 10 cm.
This is an example. Type the numbers from your problem to start.
Start mark
example
Length
answer
End mark
example
Number sentences
10 = 3 + 7
Good to know
•
The object doesn’t start at 0. It starts at another mark.
•
Take the start mark away from the end mark.
•
Count the spaces between marks, not the marks.
Step-by-step
WE KNOW
Start mark: 3 cm
End mark: 10 cm
FIND
length
Step 1 · Find length
10 = 3 + ?
Count the spaces from the start mark to the end mark.
10 − 3
Count the spaces: 4, 5, 6, 7, 8, 9, 10 → 7
Length: 7 cm
Check
Put the numbers back in. Both sides should match.
10 = 3 + 7 ✓
Topic check
See what you know: 5 questions on this topic
New questions each time. Pass to mark it complete.
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