Pick an island which has an area over 100,000 sq km than and island smaller than 100,000 sq km, then repeat until you get one wrong or get them all. In the quiz there are 18 islands over 100,000 sq km, ranging from 101,826 to 2,130,800 sq km and 18 islands under 100,000 sq km ranging from 8,350 to 97,530 sq km. (If it helps, For reference, the nation of South Korea has a land area of 99,909 sq km. Or the US state of Kentucky has a land area of 102,269 sq km)
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