62.50%
37.50%
60%
40%
Let the saving invested in first part be \(x\) and saving invested in second part be \(y\).
Given that,
\(\frac {x\times 15\times 4}{100}=\frac {y\times 12\times 3}{100}\)
\(x\times 15\times 4=y\times 12\times 3\)
\(60x=36y\)
\(\frac xy=\frac {36}{60}\)
\(\frac xy=\frac {3}{5}\)
Required percentage,
\(= \frac {x}{x+y}\times100\)
\(= \frac {3}{3+5}\times100\)
\(= \frac {3}{8}\times100\)
\(=37.50 \%\)
So, the correct option is (B): \(37.50\)
For any natural number $k$, let $a_k = 3^k$. The smallest natural number $m$ for which \[ (a_1)^1 \times (a_2)^2 \times \dots \times (a_{20})^{20} \;<\; a_{21} \times a_{22} \times \dots \times a_{20+m} \] is: