Understand Compound Interest for the 2nd Year

The interest earned exclusively during the second year is given by the formula: $I_2 = P \cdot \left(1 + \frac{R}{100}\right)^{2-1} \cdot \frac{R}{100}$.

$I_2 = P \times \left(1 + \frac{R}{100}\right) \times \frac{R}{100}$

Substitute the Given Values

Given $R = 10\%$ and $I_2 = 9911$, substitute these values into the formula.

$9911 = P \times \left(1 + \frac{10}{100}\right) \times \frac{10}{100}$

Simplify the Expression

Simplify the fractions: $\left(1 + \frac{10}{100}\right) = 1.1$ and $\frac{10}{100} = 0.1$.

$9911 = P \times 1.1 \times 0.1$

Calculate the Principal ($P$)

Multiply $1.1 \times 0.1 = 0.11$, then solve for $P = \frac{9911}{0.11}$.

$P = \frac{9911}{0.11} = 90100$