其它
Last month, the price of a couch increased by $\textbackslash$600$. During a sale this month, the couch was offered at a $25\textbackslash\%$ discount. John bought the couch at $\textbackslash$2250$ at the sale. What is the percentage decrease in the cost of the couch as compared to the original price of the couch before the discount? 
Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages
Price before discount $=\frac{100}{75}\times\textbackslash$2250=\textbackslash$3000$  Original price of the couch before increase $=\textbackslash$3000-\textbackslash$600=\textbackslash$2400$  Price decrease $=\textbackslash$2400-\textbackslash$2250=\textbackslash$150$  Percentage decrease $=\frac{\textbackslash$150}{\textbackslash$2400}\times100\textbackslash\%=6.25\textbackslash\%$ 