In a school, 200 students participated in a talent show. Each student participated in at least one of the following three events: Singing, Dancing, and Acting. If 120 students participated in Singing, 100 students participated in Dancing, 70 students participated in Acting, 50 students participated in both Singing and Dancing, 30 students participated in both Singing and Acting, 20 students participated in both Dancing and Acting, and 10 students participated in all three events, how many students participated only in Singing? Let's think step by step and output the final answer within \boxed{}.
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