The compound interest on Tk. 10,000 at 10% per annum for a certain period is Tk. 2,100. The time period (in years) is -

Question: The compound interest on Tk. 10,000 at 10% per annum for a certain period is Tk. 2,100. The time period (in years) is -

Solution:
Principal amount, P = 10,000 taka
Compound Interest, I = 2100 taka

So, Total amount, A = 12100 Taka
r = 10% = 0.1

Now, (1.1)² = 1.21
So, n = 2 (Time period)