Sarah is organizing a charity run event. She expects 50 participants to sign up. However, she knows from previous events that 20% of the expected participants usually do not show up on the day of the event. She also wants to prepare for unexpected participants and estimates that an additional 10% of the expected participants might show up without prior registration. If Sarah decides to prepare gift bags for each participant, how many gift bags should she prepare? Let's think step by step and output the final answer within \boxed{}.
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