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Post any questions within the scope and level of Mathematics (2 unit). Once a question is posted, it needs to be answered before the next question is raised.
I encourage all current students in particular to participate in this marathon.
To get the ball rolling:
![](https://latex.codecogs.com/png.latex?\bg_white $Suppose that a person receives an income of $A$ at the beginning of every year which is deposited into a bank account. The bank account earns an interest rate of $100r_1$ per cent per annum. However, just before he deposits his income into the bank account each year, he withdraws $100r_2$ per cent of his balance for everyday expenses.\\\\Explain why this person must choose the proportion of his withdrawal $r_2$ to be such that $r_2<\dfrac{r_1}{1+r_1}$ in order to ensure that his savings balance grows at a divergent rate over time (otherwise his savings will never exceed a certain value).$)
I encourage all current students in particular to participate in this marathon.
To get the ball rolling: