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$$\left.0,0891\cdot e^{-0,0044x} = 0,019602\cdot e^{0,00004x} \quad\right|\;:0,019602$$$$\left.\frac{0,0891}{0,019602}\cdot e^{-0,0044x} =e^{0,00004x} \quad\right|\;\cdot e^{+0,0044x}\;\;;\;\;\frac{0,0891}{0,019602}=\frac{50}{11}$$$$\left.\frac{50}{11}=e^{0,00004x}\cdot e^{0,0044x} \quad\right|\;\text{Potenzgesetz }a^x\cdot a^y=a^{x+y}$$$$\left.\frac{50}{11}=e^{0,00004x+0,0044x} \quad\right|\;\text{Exponenten addieren}$$$$\left.\frac{50}{11}=e^{0,00444x} \quad\right|\;\ln(\cdots)$$$$\left.\ln\left(\frac{50}{11}\right)=0,00444x\quad\right|\;:0,00444$$$$\left.x=\frac{\ln\left(\frac{50}{11}\right)}{0,00444}\approx341,01976\quad\right.$$