Question

Separately, Jack and Sristi invested the same amount of money in a stock market. Jack’s invested amount kept getting reduced by 50% every month. Sristi’s investment also reduced every month, but in an arithmetic progression with a common difference of Rs. 15000. They both withdrew their respective amounts at the end of the sixth month. They observed that if they had withdrawn their respective amounts at the end of the fourth month, the ratio of their amounts would have been the same as the ratio

Accepted Answer

A. Let initial investment = $A$. Jack's amount after $n$ months = $A / 2^n$. Sristi's amount after $n$ months = $A - 15000n$. At month 4: Jack: $A / 16$, Sristi: $A - 60000$. At month 6: Jack: $A / 64$, Sristi: $A - 90000$. Ratio equality: $\frac{A / 16}{A - 60000} = \frac{A / 64}{A - 90000} \implies \frac{4}{A - 60000} = \frac{1}{A - 90000} \implies 4A - 360000 = A - 60000 \implies 3A = 300000 \implies A = 100000$.

Stock Market Investments Comparison

Explanation

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