How long (in years) will a sum of money invested at 6% per annum simple interest to increase its value by 40%?

Interest rate, R = 6% per annum

Increase in value = 40%, which means the interest is 40% of the principal amount.

We are to find the time T in years.

The formula for Simple Interest (SI) is:

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

where:

SI is the simple interest,

P is the principal (initial amount),

R is the rate of interest per annum,

T is the time in years. 

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