Question: What is the greatest common divisor of the number of ice layers in a core sampled over 320 days and 240 years, assuming one layer forms annually? - Parker Core Knowledge

Understanding the Context

Why This Question Is Capturing Attention in the US

This line of inquiry resonates with growing public interest in climate change and global environmental trends. Americans, especially those following science and sustainability topics, are noticing how daily measurements translate into long-term data—especially with ice cores that preserve atmospheric history for centuries. The pairing of short-term sampling (320 days) with century-scale ice accumulation (240 years) presents a tangible numerical puzzle that speaks to curiosity about how conditions accumulate over time.

Amid heightened awareness of the accelerating climate crisis, technical questions about dating methods, data patterns, and measurement reliability gain real-world relevance. The number puzzle isn’t just academic—it reflects how scientists extract meaningful timelines from layered ice, where each layer holds a fragment of atmospheric history. For educators, researchers, and informed citizens, understanding GCD in this context deepens appreciation of how precise data underpins climate projections and policy decisions.

Key Insights

How the Greatest Common Divisor Actually Works in This Case

The Greatest Common Divisor (GCD) identifies the largest integer that divides evenly into both numbers. Here, the two numbers are:

• The number of days: 320
• The number of years: 240

Since one layer forms annually, the total number of ice layers over these periods is simply 320 and 240, respectively. To find the GCD of 320 and 240, we factor each number:

• 320 = 2⁶ × 5
• 240 = 2⁴ × 3 × 5

Final Thoughts

The common prime factors with the lowest exponents are 2⁴ and 5. Multiplying these gives:
GCD = 16 × 5 = 80

Thus, 80 is the