Perimeter for 4th Grade
Perimeter is the distance around a shape. For fourth graders, finding perimeter usually means adding the lengths of all the sides of a polygon. For a rectangle, we can add the four sides, or use the formula: perimeter = 2 × length + 2 × width (or 2 × (length + width)). For a square, we multiply one side length by 4.
Perimeter is measured in linear units: inches, feet, yards, centimeters, or meters. Real-world uses include putting a fence around a yard, framing a picture, or running around the edge of a field. Understanding perimeter helps students connect math to everyday situations.
DETAILED EXPLANATION
To find the perimeter of any polygon, add the lengths of every side. If some sides are equal (like in a rectangle or square), we can use shortcuts. For a rectangle with length L and width W, the perimeter is 2L + 2W because there are two lengths and two widths. For a square with side s, the perimeter is 4s.
Sometimes not all side lengths are given. If we know a rectangle has one side of 7 cm and another of 4 cm, we know the opposite sides are the same, so the perimeter is 7 + 4 + 7 + 4 = 22 cm, or 2 × (7 + 4) = 22 cm.
The Absolute Best Book to Ace Grade 4 Math
WORKED EXAMPLES WITH STEP BY STEP SOLUTIONS
Example 1
A rectangle has length 12 meters and width 8 meters. Find the perimeter.
Solutions:
Step 1: A rectangle has two lengths and two widths. So we add: 12 + 12 + 8 + 8.
Step 2: 12 + 12 = 24 and 8 + 8 = 16. So 24 + 16 = 40 meters.
Alternatively: Perimeter = 2 × (length + width) = 2 × (12 + 8) = 2 × 20 = 40 meters.
Answer: 40 meters
Mastering Grade 4 Math Word Problems
Example 2
A square has a side length of 9 centimeters. What is its perimeter?
Solutions:
Step 1: A square has four equal sides. So perimeter = 4 × side length.
Step 2: 4 × 9 = 36.
Answer: 36 centimeters
Mastering Grade 4 Math
Related to This Article
More math articles
- How to Help Your 4th Grade Student Prepare for the West Virginia WVGSA Math Test
- Mastering the Art of Integration: Vector-Valued Functions Explored
- How to Prepare for the Pre-Algebra Test?
- The Ultimate SSAT Middle-Level Math Course (+FREE Worksheets & Tests)
- Understanding Fractions Definition
- “Great Resignation” Regret: People Who Want Their Old Jobs Back
- From Equations To Innovation: Math Careers That Quietly Run The World
- 6th Grade MEAP Math Practice Test Questions
- How to Multiply and Divide Fractions? (+FREE Worksheet!)
- 10 Most Common 3rd Grade SBAC Math Questions
What people say about "Perimeter for 4th Grade - Effortless Math: We Help Students Learn to LOVE Mathematics"?
No one replied yet.