# Estimating answers (age 9+)

Apply the area formula (l × w) and perimeter formula (2l + 2w) for rectangles including squares in real-world and mathematical problems; calculate and compare areas using standard units (cm², m²) and estimate areas of irregular shapes

Builds on: Understanding angles (age 8+) (hard, https://ai.page/c/understanding-angles-age-8-maths/en.md), Perimeters of polygons (hard, https://ai.page/c/perimeters-of-polygons/en.md)

Concept id: estimating-answers-age-9. Subject: maths. Licence: CC BY-SA 4.0.

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