How do you find q1?

In order to find Q1, you must first find Q2. Q2 is the median, or middle, for the entire set of given data. If the data set is 1, 2, 2, 3, 3, 4, 4 ,4, 5, 5, 6, 7, 7, then Q2 would be 4. Therefore, the first half of the data set is 1, 2, 2, 3, 3, 4. Q1 is the median for the first half of data. Since there are an even number of entries for the first half, the two middle numbers are averaged. Thus, 2+3=5, and 5/2=2.5. Q1 equals 2.5.