What is the median of a set with 9 distinct numbers?
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Question: How many pairs of non-congruent triangles can be formed, given that they share an equal side and two equal angles?
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What is the average weight of 20 students in a class if their weights are 120, 130, 135, 140, 125, 130, 135, 150, 155, 125, 130, 140, 135, 130, 145, 160, 155, 150, 135, and 140 pounds?