Question: A glaciologist studies 8 ice cores from different glaciers. If 3 cores are selected at random for isotopic analysis, how many ways can they be chosen such that at least 2 cores are from the same region, given that 4 cores are from the Arctic and 4 from the Antarctic?

Mon, 04 May 2026 02:16:53 +0000

**A Glaciologist Studies 8 Ice Cores—Here’s How Many Ways 3 Can Be Selected with at Least Two from the Same Region** In a climate-conscious era, understanding the hidden stories beneath glaciers has become more than scientific curiosity—it’s critical to tracking Earth’s past and future. A key method involves analyzing ice cores extracted from polar ice sheets, offering clues about ancient climates and atmospheric shifts. Recently, researchers drew attention by studying a collection of eight ice cores: four from the Arctic region and four from the Antarctic. When selecting just three cores at random for isotopic analysis, scientists face a mathematical question: how many ways can they choose the cores so that at least two come from the same geographic region? This insight matters not only to glaciologists but also to anyone interested in climate science, data-driven decision-making, and environmental stewardship—especially as extreme weather and melting ice become central global concerns. ---