In how many years will Rs. 2,500 invested at the rate of 16% p.a. simple interest, amount to Rs. 4,100?

Principal (P) = Rs. 2,500

Rate of interest (R) = 16% per annum

Amount (A) = Rs. 4,100

​$$\text{SI} = \frac{P \times R \times T}{100}$$​​

A = P + SI

Where, A = amount, P = principal, R = rate of interest, T = time, SI = simple interest.

SI = A – P = 4100 – 2500 = 1600

Now, Putting the values in SI formula;

​$$1600 = \frac{2500 \times 16 \times t}{100}$$​​

​$$1600 = 400 \times t$$​​

​$$t = \frac{1600}{400} = 4$$​​

Thus, The investment will amount to Rs. 4,100 in 4 years.