Practice Questions
Concept Explanation
Perimeter is the total distance around a closed 2D figure, measured in cm or m.
Formulas
- Square: 4 × side
- Rectangle: 2(length + breadth)
- Triangle: sum of three sides
- Circle (circumference): 2πr
- Semicircle perimeter: πr + 2r
Example
Rectangle 12 cm × 5 cm: perimeter = 2(12 + 5) = 34 cm.
Common Trap
Semicircle perimeter includes the diameter, not just the curved arc.
-
Q1 Easy
Perimeter of a square with side 9 cm is:
ExplanationPerimeter = 4 × 9 = 36 cm. -
Q2 Easy
Perimeter of a rectangle 15 cm × 7 cm is:
ExplanationPerimeter = 2(15 + 7) = 44 cm. -
Q3 Easy
A triangle has sides 6 cm, 8 cm and 10 cm. Perimeter is:
ExplanationPerimeter = 6 + 8 + 10 = 24 cm. -
Q4 Easy
Circumference of a circle, radius 7 cm, π = 22/7, is:
ExplanationCircumference = 44 cm. -
Q5 Easy
An equilateral triangle has side 11 cm. Perimeter is:
ExplanationPerimeter = 3 × 11 = 33 cm. -
Q6 Medium
A rectangular garden 25 m × 18 m is fenced once. Fence length needed is:
ExplanationPerimeter = 2(25 + 18) = 86 m. -
Q7 Medium
Semicircle radius 7 cm, π = 22/7. Perimeter (arc + diameter) is:
ExplanationArc 22 cm + diameter 14 cm = 36 cm.
-
Q8 Medium
A wire 132 cm long (π = 22/7) forms a circle. Radius is:
Explanation2 × 22/7 × r = 132, so r = 21 cm. -
Q9 Medium
Perimeter of a regular pentagon with side 8 cm is:
ExplanationPerimeter = 5 × 8 = 40 cm. -
Q10 Medium
A square and equilateral triangle have equal perimeter 36 cm. Side of square is:
ExplanationSquare side = 36/4 = 9 cm. -
Q11 Hard
Cost of fencing a square field of side 50 m at Rs. 12 per m is:
ExplanationPerimeter = 200 m. Cost = 200 × 12 = Rs. 2400. -
Q12 Hard
An isosceles triangle has equal sides 13 cm and base 10 cm. Perimeter is:
ExplanationPerimeter = 13 + 13 + 10 = 36 cm. -
Q13 Easy
A rhombus has side 12 cm. Perimeter is:
ExplanationAll sides equal: 4 × 12 = 48 cm. -
Q14 Hard
Circumference is 62.8 cm, π = 3.14. Diameter is:
Explanationd = 62.8/3.14 = 20 cm.
-
DS1 Easy
What is the perimeter of the rectangle?
Statement ILength is 20 cm.
Statement IIBreadth is 9 cm.
ExplanationNeed both: perimeter = 58 cm. -
DS2 Easy
What is the circumference of the circle? (π = 22/7)
Statement IRadius is 14 cm.
Statement IIDiameter is 28 cm.
ExplanationEach alone gives circumference = 88 cm.
-
DS3 Medium
What is the perimeter of the equilateral triangle?
Statement IOne side is 14 cm.
Statement IIAll sides are equal.
ExplanationStatement I alone: perimeter = 42 cm. Statement II alone gives no side length. -
DS4 Medium
What is the fencing cost at Rs. 15 per m for a square field?
Statement ISide is 40 m.
Statement IIPerimeter is 160 m.
ExplanationEach alone: cost = 160 × 15 = Rs. 2400.