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 if sales returns and allowances were​ $136?

1 answer

280 + 0.06(s-136-5000) = $328.54.
280 + 0.06s-308.16 = 328.54,
0.06s - 28.16 = 328.54,
S = $5945. = Gross sales.