11th OG 92题

In a certain funiture store, each week Nancy earns a salary of $240 plus 5 percent of the amount of her total sales that exceeds $800 for the week. If Nancy earned a total of $450 one week, what were her total sales that week?

$2,200       $3,450         $4,200         $4, 250       $5,000

key is 5000. 请问我以下的做法那里错了：

450-240=190

190/0.05=3800

所以说那个星期他应该总共卖了＄3800拉？

啊，我实在不敢相信我竟然~~~~~~~~~~~

谢谢楼上的了