Neil invested a total of ${\11{,}000}$ in two accounts. After a year, one account had earned $12.2\%$, while the other account had lost $7.9\%$. In total, Neil had a net gain of ${\839.50}$. How much money did Neil invest in each account?
Neil invested in the account that grew by $12.2\%$.
Neil invested in the account that fell by $7.9\%$.