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UKMT Senior Kangaroo, 2025

Algebra Difficulty 3.0 AMC 10/12 Prove it United Kingdom

The length of one side of a rectangular park was increased by $20\%$ , while the length of the other side was increased by $50\%$ . After the changes the park is now square in shape. The shaded area shown between the two diagonals in the diagram is $210$ . What was the original area of the park before the changes were made?

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