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Geometry Difficulty 2.0 Junior Find the answer
Rectangle ABCD, pictured below, shares 50% of its area with square EFGH. Square EFGH shares 20% of its area with rectangle ABCD. What is ADAB?
Pick one
Solution
If we shift A to coincide with E, and add new horizontal lines to divide EFGH into five equal parts:
This helps us to see that AD=a/5 and AB=2a, where a=EF.
Hence ADAB=a/52a=10.
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