A loan of $L$ is taken over ten years and will be repaid using the sinking fund method with equal size

quarterly payments $($i$.$e$.$ end of quarter$)$ each of size $387\mathrm{.}57$ at a nominal annual interest rate of $q\%$

compounded quarterly. The outstanding balance for this loan after the ${20}^{th}$ payment is $0\mathrm{.}59774$ L $.$

Calculate L$.$ Give your answer rounded to the nearest whole number $($i$.$e$.$ X$).$