Passage Summary: Even though City X is half as big as City Y, it has way fewer people in the hospital than you'd expect—only a quarter as many as City Y.

Reasoning: City X is half the size of City Y, yet its hospital patient count is disproportionately low, at only one-quarter of City Y's count.

Analysis: We are looking for a reason why City X has a disproportionately low number of hospital patients compared to its population size. If City X is half the size of City Y, we might expect it to have half the patients, but it only has a quarter; this suggests City Y has a much higher 'patient-per-person' rate. Look for factors like City Y having older residents, more dangerous industries, or perhaps City Y's hospitals serving the surrounding region while City X's do not. The 'except' answer will be the one that fails to explain this 2:1 vs 4:1 discrepancy.