The price ratio of goods $$A$$ to $$B$$ is $$7:2$$. If their prices were increased by $$\textbackslash$60$$ respectively, the price ratio would be $$5:2$$. What are the prices of these two goods? 
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The price difference between the two goods did not change.  Before $\to$ $$A:B:Difference$$ is $$7:2:5$$  After $\to$ $$A:B:Difference$$ is $$5:2:3$$  $\textasciitilde$  Make difference the same number of units in both ratios by finding LCM.  Before $\to$ $$A:B:Difference$$ is $$21:6:15$$  After $\to$ $$A:B:Difference$$ is $$25:10:15$$  $\textasciitilde$  Therefore,  $$4u=\textbackslash$60$$  $$1u=$$ $$\textbackslash$60\div4=\textbackslash$15$$  $\textasciitilde$  The original prices of these two goods were  $$A=21u=21\times15=\textbackslash$315$$ and  $$B=6u=6\times15=\textbackslash$90$$. 