Institution: Bank Asia Ltd Exam: Bank Asia Ltd - Trainee Officer - 28.10.2016 ||
Topic: Arithmetic Mathematics (পাটিগণিত), Subject: Mathematics (সাধারণ গণিত)

Best Answer Explained in Below-:

To calculate the compound interest on Tk. 10,000 for 4 years at an annual interest rate of 5%, we can use the formula for compound interest:

\[ A = P (1 + r)^n \]

Where:
- \( A \) is the amount of money accumulated after n years, including interest.
- \( P \) is the principal amount (initial investment).
- \( r \) is the annual interest rate (decimal).
- \( n \) is the number of years the money is invested for.

In this case, \( P = 10,000 \), \( r = 0.05 \) (5%), and \( n = 4 \).

Plugging in the values, we have:

\[ A = 10,000 (1 + 0.05)^4 \]
\[ A = 10,000 (1.05)^4 \]
\[ A \approx 10,000 \times 1.21550625 \]
\[ A \approx 12,155.06 \]

Now, to find the compound interest, we subtract the principal from the total amount:

\[ \text{Compound Interest} = A - P \]
\[ \text{Compound Interest} = 12,155.06 - 10,000 \]
\[ \text{Compound Interest} \approx 2,155.06 \]

Rounding this amount approximately gives us Tk. 2155, which aligns with option C. This option is the closest to our calculated value, making it the correct answer.