{18, 17, 10, 25, 20, 20, 30, 18, 18, 30, 25}
put in order
10, 17, 18, 18, 18, 20, 20, 25, 25, 30, 30
so
median = 20
Lower IQR = (10+17+18+18+18)/5 = 81/5 = 16.2
Upper IQR = (20+25+25+30+30)/5 = 130/5 = 26
interquartile range = 26 - 16.2 = 9.8
answer
interquartile range = 9.8
