SME
Grade 3 Math · Problem type
Perimeter of shapes with equal sides
Use this for “A sign has 8 equal sides of 12 inches. What is its perimeter?”
Diagram
A hexagon: 6 sides, 6 corners
Perimeter: 6 × 5 cm = 30 cm all the way around
Side length: 5 cm
This is an example. Type your own values to start a new problem.
Sides
×
Side length (cm)
=
Perimeter (cm)
Formulas
6 × 5 = 30
Sides × side length = perimeter
Assumptions
•
Every side is the same length.
•
Add the side once for each side: that is sides × side length.
Step-by-step
WE KNOW
Sides: 6
Side length: 5 cm
FIND
perimeter
Step 1 · Find perimeter
6 × 5 = ?
Sides × side length = perimeter
Multiply the sides by the side length.
5 × 5 = 25
One more group: 25 + 5 = 30
Perimeter = 30 cm
Check
Put the numbers back in. Both sides should match.
6 × 5 = 30 ✓
Topic check
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