Solved Questions on Perimeter of Closed Figures
1. What is the perimeter of an irregular hexagon with sides of length 5 cm, 8 cm, 4 cm, 6 cm, 7 cm, and 9 cm?
a) 39 cm
b) 39.5 cm
c) 40 cm
d) 40.5 cm
Answer: a) 39 cm
Explanation: To find the perimeter of an irregular polygon, we need to add up the lengths of all its sides.
Substituting the given values, we get P = 5 + 8 + 4 + 6 + 7 + 9 = 39 cm.
2. What is the perimeter of a regular octagon with sides of length 4 cm?
a) 32 cm
b) 16 cm
c) 8√2 cm
d) 16√2 cm
Answer: a) 32 cm
Explanation: The formula for the perimeter of a regular polygon with n sides, each of length s, is P = n×s.
Substituting the given values, we get P = 8(4) = 32 cm.
3. A kite has a perimeter of 28 cm. If one pair of adjacent sides has lengths of 6 cm and 6 cm, what are the lengths of the other two sides?
a) 8 cm and 8 cm
b) 6 cm and 14 cm
c) 8 cm and 12 cm
d) 10 cm and 10 cm
Answer: a) 8 cm and 8 cm
Explanation: Since a kite has two pairs of adjacent sides that are equal in length, and the Perimeter is 28 cm, we can use the formula for the perimeter of a kite to set up an equation:
28 = 2x + 2y
28 = 2(6) + 2y
16 = 2y
y = 8 cm
So, the lengths of the other pair of adjacent sides are 8 cm and 8 cm.
4. A circular track has a circumference of 440 metres. What is the length of one complete lap (the distance travelled when running around the track once)?
a) 70 metres
b) 110 metres
c) 220 metres
d) 440 metres
Answer: d) 440 metres
Explanation: The circumference of the track is the distance travelled around the track once, so one complete lap is equal to the circumference = 440 metres
5. Find the perimeter of a trapezium with parallel sides of length 5 cm and 7 cm, and non-parallel sides of length 4 cm and 6 cm.
a) 20 cm
b) 22 cm
c) 24 cm
d) 26 cm
Answer: b) 22 cm
Explanation: The perimeter of a trapezium is the sum of the lengths of all its sides. In this case, the parallel sides have lengths of 5 cm and 7 cm, and the non-parallel sides have lengths of 4 cm and 6 cm.
Therefore, the perimeter is: Perimeter = 5 cm + 7 cm + 4 cm + 6 cm = 22 cm.
Practice Questions on Perimeter of Closed Figures
1. What is the formula for finding the perimeter of a square?
a) P = 2 x side
b) P = 4 x side
c) P = l + b
d) P = l x b
Answer: b) P = 4 x side
2. What is the perimeter of a rectangle with a length of 5 cm and a width of 3 cm?
a) 18 cm
b) 16 cm
c) 15 cm
d) 20 cm
Answer: b) 16 cm
3. What is the perimeter of a kite with side lengths of 8 cm and 12 cm?
a) 16 cm
b) 20 cm
c) 32 cm
d) 40 cm
Answer: d) 40 cm
4. What is the perimeter of an equilateral triangle with a side length of 6 cm?
a) 12 cm
b) 9 cm
c) 18 cm
d) 15 cm
Answer: c) 18 cm
5. If the circumference of a circle is 18π units, what is its radius?
a) 3 units
b) 6 units
c) 9 units
d) 18 units
Answer: c) 9 units
6. What is the perimeter of a regular hexagon with side length 5 cm?
a) 10 cm
b) 15 cm
c) 30 cm
d) 25 cm
Answer: c) 30 cm
7. The diameter of a circle is 20 cm. What is its circumference? (approx.)
a) 3.14 cm
b) 6.28 cm
c) 31.4 cm
d) 62.8 cm
Answer: d) 62.8 cm
8. What is the perimeter of a rectangle with a length of 6 units and a width of 4 units?
a) 10 units
b) 16 units
c) 18 units
d) 20 units
Answer: d) 20 units
9. What is the perimeter of a triangle with sides of 4 units, 5 units and 6 units?
a) 15 units
b) 14 units
c) 16 units
d) 17 units
Answer: a) 15 units
10. What is the perimeter of a hexagon with a side length of 3 units?
a) 18 units
b) 16 units
c) 15 units
d) 19 units
Answer: a) 18 units
