Silvio's gross earnings for last week were $328.54. His remuneration consists of a base salary of $280 plus a commission of 6% on net sales exceeding his weekly quota of $5000. What were Silvio's gross sales for the week
Let X be Silvio's gross sales for the week.
His commission is 0.06 * (X - 5000).
His total remuneration is 280 + 0.06 * (X - 5000).
280 + 0.06 * (X - 5000) = 328.54.
0.06 * (X - 5000) = 328.54 - 280 = 48.54.
(X - 5000) = 48.54 / 0.06 = 809.
X = 809 + 5000 = 5809.
Silvio's gross sales for the week were $5809. Answer: \boxed{5809}.