Dani has three cats: Binkie, Frankie, and Spaatz. Each cat has a collar decorated with gemstones. Binkie has three times as many gemstones on his collar as Frankie, but Spaatz has five fewer gemstones on her collar than Frankie. If Frankie has 8 gemstones on his collar, how many gemstones does Binkie have on his collar? Let's think step by step and output the final answer within \boxed{}.
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