The cost of $$3$$ pieces of chocolate cake is equal to the cost of $$2$$ pieces of cheesecake. The cost of $$3$$ pieces of cheesecake is equal to the cost of $$5$$ cookies. If $$1$$ cookie costs $$ $9$$, how much does $$1$$ piece chocolate cake cost? $$ $$$~\uline{~~~~~~~~~~}~. 
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