$7\mathrm{.}14.$ Saira Banu turns $15$ today. Her elder sister, who is enrolled in engineering

economics, has helped her appreciate the power of compounding in building up equity.

Saira decided to set aside the cash gift from her grandparents' trust at each birthday,

beginning the ${16}^{th}$ and ending with the ${55}^{th}.$ The trust provides a dollar gift ten times her

age. If her savings can earn an annually compounded interest rate of $10\%$ per year, how

much will have accumulated on her ${60}^{th}$ birthday? Though she does not save beyond the

${55}^{th}$ birthday, the savings continue to earn compounded interest.

Answer: $$178,947$