You currently have $$7,800($Present Value$)$ in an account that has an interest rate of $7\mathrm{.}5\%$ per year compounded semi$-$annually $(2$ times per year$).$ You want to withdraw all your money when it reaches $$12,480($Future Value$).$ In how many years will you be able to withdraw all your money?

The number of years is

Round your answer to $1$ decimal place.