Interest 37571

We will deposit € 10,500 at the bank at 1.1% interest, and we want to withdraw € 11,000. How many years do we have to wait? Round to 2 decimal places.

Correct answer:

n =  4.25

Step-by-step explanation:

$$\begin{gathered} a=10500\text{Eur} \\ b=11000\text{Eur} \\ q=100\%+1.1\%=1+\frac{1.1}{100}=1.011 \\ a\cdot q^n=b \\ n\log q=\log b/a \\ n=\log (b/a)/\log q=\log (11000/10500)/\log 1.011=4.25 \end{gathered}$$

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