Question

The times in minutes it took 16 students to complete a logic puzzle are listed below. Find the median, the upper and lower quartiles, the interquartile range, and the range of the data. {15, 11, 9, 15, 12, 10, 18, 16, 14, 22, 13, 20, 17, 12, 18, 19}

Answer 1

first thing...put the numbers in order ...
9,10,11,12,12,13,14,15,15,16,17,18,18,19,20,22

Q1 (lower quartile) = 12
Q2 (median) = 15
Q3 (upper quartile) = 18
IQR = Q3 - Q1 = 18 - 12 = 6
range = (highest number - lowest number) = 22 - 9 = 13