An environmental study measures the decrease in a pollutant concentration from 150 ppm to 90 ppm over 8 months. Assuming a linear decrease, what is the monthly rate of decrease?

Thu, 30 Apr 2026 18:54:29 +0000

Title: Understanding Environmental Decline: How Linearly Measured Pollutant Reduction Reveals Monthly Rates Environmental monitoring plays a pivotal role in assessing air and water quality improvements, helping policymakers and scientists track the effectiveness of pollution control measures. One key metric is the reduction in pollutant concentration over time—especially when measured precisely and consistently. In a recent environmental study, a significant drop in a harmful pollutant was observed: carbon monoxide levels decreased from 150 parts per million (ppm) to 90 ppm over a period of 8 months. But how fast was the pollutant truly decreasing each month? And what does a linear trend reveal about this environmental recovery? ### Tracking the Decline: Linear Decrease Explained
To understand the monthly rate of decrease, we apply basic linear modeling. Assuming a consistent, steady reduction—linear over time—the change follows a straight-line relationship between pollutant concentration and time. The initial concentration is:
Initial pollutant = 150 ppm