Perimeter and Area — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. A rectangle is 9 cm long and 4 cm wide. What is its area?
A) 13 square cm
B) 26 square cm
C) 36 square cm
D) 32 square cm
Area means length times width: 9 × 4 = 36 square cm. So 36 unit squares fit inside the rectangle.
2. What is the perimeter of a rectangle with sides 8 m and 5 m?
A) 40 m
B) 13 m
C) 21 m
D) 26 m
Perimeter adds all four sides: 8 + 5 + 8 + 5 = 26 m. You can also double 8 + 5 = 13 to get 26 m.
3. Two rectangles both have a perimeter of 24 cm. Which could have the greater area?
A) 1 cm × 11 cm
B) 2 cm × 10 cm
C) 3 cm × 9 cm
D) 5 cm × 7 cm
Rectangles with the same perimeter can have different areas, and the one closest to a square holds the most space. The 5 by 7 rectangle has area 35 square cm, larger than 11, 20, or 27 from the other choices.
4. Which unit is used to measure area?
A) centimeters
B) meters
C) square meters
D) inches
Area counts how many unit squares fit inside, so it uses square units like square meters. Plain meters or centimeters only measure length, not space.
Part B: Fill in the Blank
Write the correct answer on each line.
1. A square with 7 m sides has an area of 49 square m.
All four sides of the square measure 7 m, so the area is 7 × 7 = 49 square m. That equals 49 one-meter squares filling the inside.
2. A rectangle 6 cm by 3 cm has a perimeter of 18 cm.
Adding the four sides gives 6 + 3 + 6 + 3 = 18 cm. Two long sides total 12 and two short sides total 6, making 18.
3. A garden is 10 feet long and 5 feet wide. Its area is 50 square feet.
Multiplying 10 × 5 = 50 finds the area in square feet. Imagine 10 rows of 5 one-foot squares lining the garden.
4. A rectangle with sides 12 m and 4 m has a perimeter of 32 m.
Perimeter is 12 + 4 + 12 + 4 = 32 m around the rectangle. Doubling 12 + 4 = 16 also gives 32.
5. A square playground has 8 m sides. Its area is 64 square m.
All four sides of the playground are 8 m, so 8 × 8 = 64 square m of space. That counts 64 one-meter squares inside the square.