Question: A climate researcher in New York City analyzes energy usage data from three boroughs. Over one week, the total CO₂ emissions were proportional to the ratios $4:7:9$. If the second borough emitted 147 metric tons, how many metric tons did the third borough emit?
["Climate Researcher Analyzes Energy Usage Across NYC’s Boroughs: A Breakdown of CO₂ Emissions", "In a recent climate study conducted by a New York City-based researcher, energy consumption and resulting CO₂ emissions across Manhattan, Brooklyn, and Queens were analyzed using real-time data collected over one week. The results revealed distinct energy usage patterns, with emissions from the boroughs distributed in a consistent ratio—4:7:9—reflecting varying population densities, industrial activity, and infrastructure efficiency.", "Understanding how emissions scale by district helps city planners prioritize sustainability initiatives and reduce the metropolitan area’s carbon footprint. Recent findings show that the second borough, Brooklyn, recorded 147 metric tons of CO₂ emissions during the week—corresponding to the middle value in the emission ratio.", "### Deciphering the Emission Ratios", "The emissions ratio among the three NYC boroughs is given as $4:7:9$. Since Brooklyn’s emissions represent the 7 parts of this proportional breakdown, researchers used this data to calculate the total emissions and isolate the third borough’s output.", "Let the common proportional factor be $x$. Then emissions per borough are:\n- First borough: $4x$ metric tons\n- Second borough (Brooklyn): $7x$ metric tons\n- Third borough (Queens): $9x$ metric tons", "Given that Brooklyn’s emissions equal 147 metric tons:\n$$\n7x = 147\n$$\nSolving for $x$:\n$$\nx = \frac{147}{7} = 21\n$$", "Now, calculate the third borough’s emissions:\n$$\n9x = 9 \ imes 21 = 189\n$$", "### Conclusion", "According to the analysis, Queens emitted 189 metric tons of CO₂ during the week—scaling proportionally within the established $4:7:9$ emission ratio. This data underscores Queens’ significant role in the city’s overall carbon output and highlights opportunities for targeted green energy investments.", "As New York City advances its climate resilience goals, ongoing data-driven research sheds light on how different boroughs contribute to emissions and informs equitable, effective sustainability strategies across all five districts.", "---", "Keywords: New York City climate research, CO₂ emissions NYC, energy usage analysis, borough emission ratios, climate data NYC, 2024 EMissions study, carbon footprint NYC, green initiatives New York, urban sustainability"]
