percentage problem for salary In $\;2002,\, 2003, \, \text{and}\; 2004\;$ the total income of Jerry was $\$36,400$. His income increased by $15\%$ each year. What was his income in $2004$? Any hints or solution will be welcome. Thanks in advance.

$ \begin{align} I_0 & : \quad \text{income earned in}\;2002.\tag{1} \\\ \\\ I_1 & = 1.15 I_0:\quad\text{income earned in}\; 2003.\tag{2} \\\ \\\ I_2 & = 1.15 I_1 = 1.15^2 I_0:\quad \text{income earned in} \; 2004.\tag{3} \end{align} $

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$$\text{Income over $3$ years}:\;\;I_0 + I_1 + I_2 = \$36{,}400$$ $$ \iff I_0 + 1.15 I_0 + 1.15^2 = I_0\underbrace{(1 + 1.15 + 1.15^2)}_{\text{sum}\; =\; 3.4725} = 36400 $$

Solve for $I_0$, the income earned in $2002$, and then compute $I_2$ (income earned in $2004),\,$ using your computed solution for $I_0$ and the relation given by $(3)$ above.