📏 Topic Summary
Perimeter is the total distance around the outside of a two-dimensional shape. To find the perimeter, you simply add up the lengths of all the sides. For example, if a rectangle has sides of 5 cm, 3 cm, 5 cm, and 3 cm, the perimeter would be $5 + 3 + 5 + 3 = 16$ cm. This worksheet will give you practice in adding the side lengths of various shapes to find their perimeters.
🧮 Part A: Vocabulary
Match the following terms with their correct definitions:
| Term |
Definition |
| 1. Perimeter |
A. The amount of space inside a shape |
| 2. Side |
B. A straight line that forms part of the boundary of a shape |
| 3. Length |
C. The measurement of something from end to end |
| 4. Rectangle |
D. A four-sided shape with opposite sides equal and four right angles |
| 5. Square |
E. The total distance around the outside of a shape |
Match the terms and definitions:
- 1 - E
- 2 - B
- 3 - C
- 4 - D
- 5 - A
➕ Part B: Fill in the Blanks
Read the paragraph below and fill in the missing words.
To find the __________ of a shape, you need to add up the __________ of all its __________. For example, if you have a __________ with sides of 4 cm each, the perimeter is $4 + 4 + 4 + 4 = $ __________ cm.
Answer Key:
- perimeter
- lengths
- sides
- square
- 16
🤔 Part C: Critical Thinking
Explain in your own words how the formula for the perimeter of a square ($P = 4s$, where $s$ is the side length) is derived from the basic principle of adding all the side lengths.
Answer:
The formula $P = 4s$ works because a square has four equal sides. Instead of adding the side length four times ($s + s + s + s$), you can multiply the side length by 4, which is a shortcut to find the perimeter. They both achieve the same result.