YSK that if an item in a store says 2/$10, this does not mean you need to buy 2 to get the deal. Unless the price tag says "Must Buy 2", the price of 1 is still $5.
from /r/YouShouldKnow
YSK，如果商店裏的商品寫着2/10美元，這並不意味着你需要買2個才能得到優惠。除非價格標籤上寫着 "必須買2"，否則1的價格還是5元。