About This Cheat Sheet

Complete guide to Area and Perimeter for competitive exams: basic concepts of perimeter (total boundary length) and area (region enclosed), formulas for square (perimeter = 4a, area = a²), rectangle (perimeter = 2(l+b), area = l×b), triangle (perimeter = a+b+c, area = ½×base×height, Heron's formula), circle (circumference = 2πr, area = πr²), semi-circle (perimeter = πr + 2r, area = πr²/2), sector of circle (arc length = θ/360 × 2πr, area = θ/360 × πr²), parallelogram (perimeter = 2(a+b), area = base×height), rhombus (perimeter = 4a, area = ½×d₁×d₂), trapezium (perimeter = a+b+c+d, area = ½×(sum of parallel sides)×height), quadrilateral general, problems on area of paths (around rectangle, inside rectangle), problems on area of cross paths, problems on area of circular rings (annulus), problems on cost of fencing (perimeter) and cost of carpeting (area), problems on area of shaded region, problems on change in area due to change in dimensions, and shortcut tricks for SSC, Banking, Railway, UPSC, and other government exams.