Area & Perimeter

Perimeter is the total distance around a figure; area is the space it encloses, always in square units. For a rectangle, Area = length × width and Perimeter = 2(length + width); a square is the special case Area = s², Perimeter = 4s. For a parallelogram, Area = base × height, where the height is the perpendicular distance between the two bases — never the slanted side. The GRE routinely runs these backward (given area and one dimension, find the other) and mixes units, so confirm every length is in the same unit before you multiply. A useful sanity check on Quantitative Comparison: for a fixed perimeter, the more square-like a rectangle is, the larger its area — a subtle but testable relationship.

✅ Solved examples

✏️ Practice — try these, take hints as needed

📝 Topic test — 8 questions

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