Difficulty: Easy
Correct Answer: 1992
Explanation:
Given data
Reasoning
 • Uzbekistan and Turkmenistan were admitted on 2 March 1992. • Georgia was admitted on 31 July 1992. • Therefore, the common year of admission for all three is 1992. 
Common pitfalls
 Answering 1991 (their independence year) or 1993 (when some other states joined).
Final Answer
 1992
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