Question

what is the upper and lower quartile of this data set 118, 124, 124, 137, 138, 138, 138, 140, 143, 150, 151, 152, 156, 158, 159, 159, 159, 160, 162, 163, 165, 169, 170 172 173, 174, 177, 178, 206

Answer 1

upper quartile = Q3

series of 29 values

Q3: (29*3)/4=21.75, the upper quartile is the 22nd value of the series, i.e. 173

(we take the immediately higher integer)

lower quartile = Q1

29/4=7.25, the lower quartile is the 8th value, i.e. 140

(we take the immediately higher integer)