Set X={a, b, c}, where a?< b < c. If the average (arithmetic mean) of a and b is 3x–13, and the average of b and c is 3x+11, what is the range of set X?_____
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Set X={a, b, c}, where a?< b < c. If the average (arithmetic mean) of a and b is 3x–13, and the average of b and c is 3x+11, what is the range of set X?_____