Withdraw 37161

We will deposit € 8,500 into the bank at 1.3% interest and withdraw € 8,700. How many years do we have to wait? Round to 2 decimal places.

Correct answer:

n =  1.8006

Step-by-step explanation:

$$\begin{gathered} a=8500\text{Eur} \\ b=8700\text{Eur} \\ q=100\%+1.3\%=1+\frac{1.3}{100}=1.013 \\ a\cdot q^n=b \\ n\log q=\log b/a \\ n=\log (b/a)/\log q=\log (8700/8500)/\log 1.013=1.8006 \end{gathered}$$

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