Distribution

Any observation must be arranged in ascending order before finding the quartiles. Three quartiles divide the observation into four parts. The first quartile is represented by Q1, the second by Q2, and the third by Q3. Q2 represents the median position or average. The quartiles divide the whole representation in such a way that 25% of the data are present lesser than the lower quartile (Q1), 50% of the data are lesser than the mean value (Q2), 75 % of the data are lower than then higher quartile (Q3). The quartiles of data can be analysed by the following:

• First Quartile(Q1) = ((n + 1)/4)th Term

• Second Quartile(Q2) = ((n + 1)/2)th Term

• Third Quartile(Q3) = (3(n + 1)/4)th Term

Interquartile Range

This is 50% of the values present in the middle. This is represented by the data present between the upper quartile and the lower quartile. This is helpful because the analysis of interquartile data gives importance to the data set by avoiding outliers, which is the data that has gone too low or too high.