Question $5[5$ points$]$

Biotech Company received an invoice of $$7,800$ dated July $24$ with terms $\frac{2}{10},\frac{n}{15}.$ Biotech Company paid $$2,500$ on August $2,$ and $$1,000$ on August $4.$ What balance is still owed after August $4?$

Click here for help computing the number of days between two dates. For full marks your answer$($s$)$ should be rounded to the nearest cent.