1. **State the problem:** We have an exponential decay model for bacteria count given by $$B_{second}(t) = 6000 \cdot \left(\frac{15}{16}\right)^t$$ where $t$ is in seconds. 2. **Interpret the decay factor per second:** The factor $\frac{15}{16}$ means the bacteria count decreases to $\frac{15}{16}$ of its previous amount every second. 3. **Find the decay factor per minute:** Since there are 60 seconds in a minute, the decay factor per minute is $$\left(\frac{15}{16}\right)^{60}$$ because the decay compounds every second. 4. **Calculate the decay factor per minute:** $$\left(\frac{15}{16}\right)^{60} = e^{60 \ln\left(\frac{15}{16}\right)}$$ 5. **Evaluate the natural logarithm:** $$\ln\left(\frac{15}{16}\right) = \ln(15) - \ln(16) \approx 2.70805 - 2.77259 = -0.06454$$ 6. **Calculate the exponent:** $$60 \times (-0.06454) = -3.8724$$ 7. **Calculate the decay factor per minute:** $$e^{-3.8724} \approx 0.0208$$ 8. **Interpretation:** Every minute, the number of bacteria decays by a factor of approximately $0.0208$, meaning it reduces to about 2.08% of its previous amount each minute. **Final answer:** Every minute, the number of bacteria decays by a factor of approximately $0.0208$.