Perimeter and Area — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. A rectangle has an area of 42 square cm. It is 7 cm long. How wide is it?
A) 5 cm
B) 6 cm
C) 7 cm
D) 8 cm
Since area = length x width, divide: 42 / 7 = 6 cm wide.
2. A playground is 15 m long and 10 m wide. What is its perimeter?
A) 25 m
B) 50 m
C) 150 m
D) 100 m
Perimeter = 15 + 10 + 15 + 10 = 50 m. You walk around all four sides.
3. Two shapes each have an area of 24 square cm. Which pair is possible?
A) 3 × 8 and 4 × 6
B) 5 × 5 and 3 × 7
C) 2 × 10 and 4 × 7
D) 6 × 5 and 3 × 9
Both 3 x 8 = 24 and 4 x 6 = 24, so both rectangles have an area of 24 square cm.
4. A tile is a 4 cm square. How many tiles cover a 12 cm by 8 cm rectangle?
A) 4 tiles
B) 6 tiles
C) 5 tiles
D) 8 tiles
The rectangle's area is 12 x 8 = 96 square cm. Each tile covers 4 x 4 = 16 square cm. So 96 / 16 = 6 tiles.
Part B: Fill in the Blank
Write the correct answer on each line.
1. A square has a perimeter of 36 cm. Each side is 9 cm long.
A square has 4 equal sides, so divide the perimeter by 4: 36 / 4 = 9 cm per side.
2. A hallway is 15 m long and 2 m wide. Its area is 30 square m.
Area = length x width, so 15 x 2 = 30 square m.
3. A rectangle is 13 cm long and 4 cm wide. Its perimeter is 34 cm.
Add all four sides: 13 + 4 + 13 + 4 = 34 cm.
4. A square garden has an area of 25 square m. Each side is 5 m.
Since 5 x 5 = 25, each side of the square garden is 5 m.
5. A driveway is 9 m long and 4 m wide. Its area is 36 square m.
Area = length x width, so 9 x 4 = 36 square m.