The rates of interest offered by two banks BOI and SBI are 8% and 44% per annum at compound interest. Mohan deposits certain but different…

Let he deposits Rs. B in BOI and Rs. S in SBI.

Amount = $(Principal\left\{ {{{\left( {1\; + \;Rate\% } \right)}^{time}}} \right\})$

Using the above formula,

Amount at BOI = B (1 + 8%)3 = B (1.08)3

Amount at SBI = S (1 + 44%)3 = S (1.44)3

After three years, the amounts become equal.

∴ B (1.08)3 = S (1.44)3

$(\begin{array}{l}
\Rightarrow {\rm{\;}}\frac{B}{S}\; = \;\frac{{{{\left( {1.44} \right)}^3}}}{{{{\left( {1.08} \right)}^3}}}\; = \;{\left( {\frac{{1.44}}{{1.08}}} \right)^3}\\
\Rightarrow {\rm{\;}}\frac{B}{S}\; = \;{\left( {\frac{4}{3}} \right)^3}\; = \;\frac{{64}}{{27}}
\end{array})$

∴ B ? S = 64 ? 27