A certain amount is lent at x% p.a. simple interest for 3 years. Instead, if the amount was lent at 3x% p.a. simple interest for ' y ' more years, then the simple interest would have been seven times the earlier interest. What is the value of y ?

Initial Interest rate = x% per annum

Time period for the first scenario = 3 years

New interest rate = 3x% per annum

The New simple interest is seven times the earlier interest when lent for 3 + y years.

The problem is based on the concept of Simple Interest (SI), which is calculated using the formula:

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

Where:

P is the principal amount

R is the rate of interest per year

T is the time in years

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