Each watermelon\textquotesingle s full price is $$4$$ dollars. Currently, the watermelons on a discounted price for $$3$$ dollars each. Ms. Lee ~wants to buy $$3$$ of them. She needs to pay~\uline{~~~~~~~~~~}~dollars in total. 
Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems->Finding the Unit Rate and then the Total Value
$$3+3+3=9$$ 