1. **Problem Statement:** You start with 40000 taka and earn a monthly profit between 10% and 15% for 2 years (24 months). We want to find the final amount after 2 years. 2. **Formula Used:** The amount after compounding monthly is given by: $$ A = P \times (1 + r)^n $$ where: - $P$ is the principal (initial amount), - $r$ is the monthly profit rate (as a decimal), - $n$ is the number of months. 3. **Calculate for 10% monthly profit:** - $P = 40000$ - $r = 0.10$ - $n = 24$ $$ A_{10\%} = 40000 \times (1 + 0.10)^{24} = 40000 \times (1.10)^{24} $$ Calculate $(1.10)^{24}$: $$ (1.10)^{24} \approx 9.8497 $$ So, $$ A_{10\%} = 40000 \times 9.8497 = 393988 $$ 4. **Calculate for 15% monthly profit:** - $r = 0.15$ $$ A_{15\%} = 40000 \times (1 + 0.15)^{24} = 40000 \times (1.15)^{24} $$ Calculate $(1.15)^{24}$: $$ (1.15)^{24} \approx 36.785 $$ So, $$ A_{15\%} = 40000 \times 36.785 = 1471400 $$ 5. **Interpretation:** After 2 years, your 40000 taka will grow to approximately between 393988 taka (at 10% monthly profit) and 1471400 taka (at 15% monthly profit). This shows the power of compound interest with high monthly returns. **Final answer:** - At 10% monthly profit: approximately 393988 taka - At 15% monthly profit: approximately 1471400 taka