In which year did the average disbursement of loans record the highest percentage increase over that of the previous year?

Step 1: Total disbursements and number of banks per year
From the table: \begin{align} \text{1982: } & \frac{118}{5} = 23.6
\text{1983: } & \frac{120}{5} = 24 \quad (\text{increase } \frac{24 - 23.6}{23.6} \approx 1.69%)
\text{1984: } & \frac{140}{5} = 28 \quad (\text{increase } \frac{28 - 24}{24} = 16.67%)
\text{1985: } & \frac{154}{5} = 30.8 \quad (\text{increase } \frac{30.8 - 28}{28} = 10%)
\text{1986: } & \frac{203}{5} = 40.6 \quad (\text{increase } \frac{40.6 - 30.8}{30.8} \approx 31.82%)
\end{align}
Step 2: Compare year-on-year percentage increases
- 1983 over 1982: \( \approx 1.69% \)
- 1984 over 1983: \( \approx 16.67% \)
- 1985 over 1984: \( \approx 10% \)
- 1986 over 1985: \( \approx 31.82% \)
Conclusion: 1986 has the highest increase.
Correction: The correct answer is (b) 1986





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: