Question: A climate change analyst in Sydney is modeling urban expansion and must select 4 districts from a list of 12, where 5 districts are designated as high-resilience zones. What is the probability that at least 2 of the selected districts are high-resilience?

Sun, 03 May 2026 22:09:27 +0000

**How Climate Resilience Shapes Sydney’s Future: A Probability Deep Dive**
As cities grapple with intensifying climate risks, Sydney’s urban planners are under growing pressure to select districts that can withstand future pressures. With urban expansion hingeing on strategic decisions, one recurring question emerges: When choosing 4 districts from 12, where 5 are marked as high-resilience zones, what’s the chance at least 2 fall in that resilient category? This doesn’t just matter for planners — it reflects broader shifts in how communities value climate preparedness. With sustainability and infrastructure security setting new urban benchmarks, understanding such probabilities helps stakeholders make informed, resilient choices. **Why This Question Is Rising in Public and Professional Circles**
Sydney’s skyline is evolving amid rising sea levels and extreme weather patterns. The city’s climate analysts are increasingly focused on identifying zones that can absorb shocks — areas designed with flood defenses, green infrastructure, and adaptive zoning. The question about selecting resilient districts taps into a growing public awareness: communities, developers, and policymakers want data-backed insights on future-proofing urban spaces. Social media discussions, municipal reports, and urban studies journals all point to growing curiosity about resilience metrics. This is no niche inquiry — it’s part of a national movement toward smarter, safer city development. **The Math Behind Strategic Selection**
To answer how likely at least 2 out of 4 selected districts are high-resilience, we apply probability based on combinatorics. From a total of 12 districts—5 high-resilience (H), 7 lower-resilience (L)—selecting 4 districts at random, the calculation involves combinations:
- Total ways to choose 4 districts: C(12, 4) = 495
- Favorable outcomes include:
- Exactly 2 H, 2 L: C(5,2) × C(7,2) = 10 × 21 = 210
- Exactly 3 H, 1 L: C(5,3) × C(7,1) = 10 × 7 = 70
- Exactly 4 H, 0 L: C(5,4) × C(7,0) = 5 × 1 = 5
- Total favorable: 210 + 70 + 5 = 285
- Probability: 285 / 495 ≈ 57.6%
This result reveals that over half of all possible selections include at least two high-resilience districts—highlighting their strategic prevalence. For data-savvy readers, this probabilistic insight supports confidence in prioritizing these zones during urban design. **What This Means in Practice**
City planners assessing resilience now rely on such models to allocate resources efficiently. Choosing at least two