SME
Grade 2 Math · Measurement & Data
Measure length in inches, feet, centimeters and meters
Use this for “One ribbon is 12 cm long. The other is 8 cm. How much longer is the first?”
Picture
Longer ribbon is 4 cm longer than Shorter ribbon.
This is an example. Type the numbers from your problem to start.
Longer ribbon
example
Shorter ribbon
example
How much longer
answer
Number sentences
4 = 12 − 8
Good to know
•
Type how long each ribbon is: the longer one, then the shorter one.
•
“A is 8 cm shorter than B” means B is the longer ribbon.
•
Measure both ribbons in the same unit.
Step-by-step
WE KNOW
Longer ribbon: 12 cm
Shorter ribbon: 8 cm
FIND
how much longer
Step 1 · Find how much longer
? = 12 − 8
Take the shorter length from the longer one, or count up from the shorter length.
8 + 2 = 10
10 + 2 = 12
Jumps: 2 + 2 = 4
How much longer: 4 cm
Check
Put the numbers back in. Both sides should match.
12 − 8 = 4 ✓
Topic check
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